diff --git a/gestioncof/autocomplete.py b/gestioncof/autocomplete.py
index 1eae6920..a9abbad7 100644
--- a/gestioncof/autocomplete.py
+++ b/gestioncof/autocomplete.py
@@ -56,22 +56,24 @@ def autocomplete(request):
     # Fetching data from the SPI
     if hasattr(settings, 'LDAP_SERVER_URL'):
         # Fetching
-        ldap_query = '(|{:s})'.format(''.join(
-            ['(cn=*{bit:s}*)(uid=*{bit:s}*)'.format(**{"bit": bit})
-             for bit in bits]
+        ldap_query = '(&{:s})'.format(''.join(
+            '(|(cn=*{bit:s}*)(uid=*{bit:s}*))'.format(bit=bit)
+            for bit in bits if bit.isalnum()
         ))
-        with Connection(settings.LDAP_SERVER_URL) as conn:
-            conn.search(
-                'dc=spi,dc=ens,dc=fr', ldap_query,
-                attributes=['uid', 'cn']
-            )
-            queries['clippers'] = conn.entries
-        # Clearing redundancies
-        queries['clippers'] = [
-            Clipper(clipper.uid, clipper.cn)
-            for clipper in queries['clippers']
-            if str(clipper.uid) not in usernames
-        ]
+        if ldap_query != "(&)":
+            # If none of the bits were legal, we do not perform the query
+            with Connection(settings.LDAP_SERVER_URL) as conn:
+                conn.search(
+                    'dc=spi,dc=ens,dc=fr', ldap_query,
+                    attributes=['uid', 'cn']
+                )
+                queries['clippers'] = conn.entries
+            # Clearing redundancies
+            queries['clippers'] = [
+                Clipper(clipper.uid, clipper.cn)
+                for clipper in queries['clippers']
+                if str(clipper.uid) not in usernames
+            ]
 
     # Resulting data
     data.update(queries)
diff --git a/gestioncof/static/css/cof.css b/gestioncof/static/css/cof.css
index 269736d0..fda55d98 100644
--- a/gestioncof/static/css/cof.css
+++ b/gestioncof/static/css/cof.css
@@ -800,7 +800,7 @@ input#search_autocomplete {
  height: 40px;
  padding: 10px 8px;
  margin: 0 auto;
- margin-top: 20px;
+ margin-top: 0px;
  display: block;
  color: #aaa;
 }
@@ -1119,3 +1119,10 @@ div.messages div.alert-success div.container {
 div.messages div.alert div.container a {
     color: inherit;
 }
+
+/* Help text */
+
+p.help-block {
+  margin: 5px auto;
+  width: 90%;
+}
diff --git a/gestioncof/templates/registration.html b/gestioncof/templates/registration.html
index 769808de..8f05dfb0 100644
--- a/gestioncof/templates/registration.html
+++ b/gestioncof/templates/registration.html
@@ -9,7 +9,9 @@
 
 {% block realcontent %}
     <h2>Inscription d'un nouveau membre</h2>
-    <input type="text" name="q" id="search_autocomplete" spellcheck="false" />
+    <p class="help-block">Les mots contenant des caractères non alphanumériques seront ignorés</p>
+    <input type="text" name="q" id="search_autocomplete" spellcheck="false"
+           placeholder="Chercher un utilisateur par nom, prénom ou identifiant clipper" />
     <div id="form-placeholder"></div>
     <div class="yourlabs-autocomplete"></div>
     <script type="text/javascript">
@@ -20,7 +22,6 @@
                 minimumCharacters: 3,
                 id: 'search_autocomplete',
                 choiceSelector: 'li:has(a)',
-                placeholder: "Chercher un utilisateur par nom, prénom ou identifiant clipper",
                 box: $(".yourlabs-autocomplete"),
             });
             $('input#search_autocomplete').bind(
diff --git a/gestioncof/templatetags/utils.py b/gestioncof/templatetags/utils.py
index 90855165..76bc6003 100644
--- a/gestioncof/templatetags/utils.py
+++ b/gestioncof/templatetags/utils.py
@@ -23,7 +23,7 @@ def key(d, key_name):
 
 
 def highlight_text(text, q):
-    q2 = "|".join(q.split())
+    q2 = "|".join(re.escape(word) for word in q.split())
     pattern = re.compile(r"(?P<filter>%s)" % q2, re.IGNORECASE)
     return mark_safe(re.sub(pattern,
                             r"<span class='highlight'>\g<filter></span>",
diff --git a/kfet/autocomplete.py b/kfet/autocomplete.py
index 64fa52cf..c0019bf9 100644
--- a/kfet/autocomplete.py
+++ b/kfet/autocomplete.py
@@ -75,22 +75,24 @@ def account_create(request):
     # Fetching data from the SPI
     if hasattr(settings, 'LDAP_SERVER_URL'):
         # Fetching
-        ldap_query = '(|{:s})'.format(''.join(
-            ['(cn=*{bit:s}*)(uid=*{bit:s}*)'.format(bit=word)
-             for word in search_words]
+        ldap_query = '(&{:s})'.format(''.join(
+            '(|(cn=*{bit:s}*)(uid=*{bit:s}*))'.format(bit=word)
+            for word in search_words if word.isalnum()
         ))
-        with Connection(settings.LDAP_SERVER_URL) as conn:
-            conn.search(
-                'dc=spi,dc=ens,dc=fr', ldap_query,
-                attributes=['uid', 'cn']
-            )
-            queries['clippers'] = conn.entries
-        # Clearing redundancies
-        queries['clippers'] = [
-            Clipper(clipper.uid, clipper.cn)
-            for clipper in queries['clippers']
-            if str(clipper.uid) not in usernames
-        ]
+        if ldap_query != "(&)":
+            # If none of the bits were legal, we do not perform the query
+            with Connection(settings.LDAP_SERVER_URL) as conn:
+                conn.search(
+                    'dc=spi,dc=ens,dc=fr', ldap_query,
+                    attributes=['uid', 'cn']
+                )
+                queries['clippers'] = conn.entries
+            # Clearing redundancies
+            queries['clippers'] = [
+                Clipper(clipper.uid, clipper.cn)
+                for clipper in queries['clippers']
+                if str(clipper.uid) not in usernames
+            ]
 
     # Resulting data
     data.update(queries)
diff --git a/kfet/static/kfet/css/index.css b/kfet/static/kfet/css/index.css
index f3e9bf8c..ce6c5be7 100644
--- a/kfet/static/kfet/css/index.css
+++ b/kfet/static/kfet/css/index.css
@@ -341,3 +341,7 @@ textarea {
 .help h4 {
     margin:15px 0;
 }
+
+.help-block {
+    padding-top: 15px;
+}
diff --git a/kfet/templates/kfet/account_create.html b/kfet/templates/kfet/account_create.html
index ac6c5daa..3b4829d8 100644
--- a/kfet/templates/kfet/account_create.html
+++ b/kfet/templates/kfet/account_create.html
@@ -23,6 +23,7 @@
           {{ trigramme_form.trigramme }}
         </div>
         <div id="trigramme_valid"></div>
+        <p class="help-block">Les mots contenant des caractères non alphanumériques seront ignorés</p>
         <input type="text" name="q" id="search_autocomplete" spellcheck="false" placeholder="Chercher un utilisateur par nom, prénom ou identifiant clipper" class="form-control">
         <div style="position:relative;">
           <div id="search_results"></div>
diff --git a/kfet/templatetags/kfet_tags.py b/kfet/templatetags/kfet_tags.py
index b3976326..c8b6a228 100644
--- a/kfet/templatetags/kfet_tags.py
+++ b/kfet/templatetags/kfet_tags.py
@@ -11,7 +11,7 @@ register = template.Library()
 
 
 def highlight_text(text, q):
-    q2 = "|".join(q.split())
+    q2 = "|".join(re.escape(word) for word in q.split())
     pattern = re.compile(r"(?P<filter>%s)" % q2, re.IGNORECASE)
     regex = r"<span class='highlight_autocomplete'>\g<filter></span>"
     return mark_safe(re.sub(pattern, regex, text))