function __performUserSearch()
 {
     include_once 'Services/Search/classes/class.ilUserSearchOptions.php';
     include_once 'Services/Search/classes/class.ilObjectSearchFactory.php';
     foreach (ilUserSearchOptions::_getSearchableFieldsInfo(!$this->isSearchableCheckEnabled()) as $info) {
         $name = $info['db'];
         $query_string = $_SESSION['rep_query']['usr'][$name];
         // continue if no query string is given
         if (!$query_string) {
             continue;
         }
         if (!is_object($query_parser = $this->__parseQueryString($query_string))) {
             ilUtil::sendInfo($query_parser);
             return false;
         }
         switch ($info['type']) {
             case FIELD_TYPE_UDF_SELECT:
                 // Do a phrase query for select fields
                 $query_parser = $this->__parseQueryString('"' . $query_string . '"');
             case FIELD_TYPE_UDF_TEXT:
                 $udf_search = ilObjectSearchFactory::_getUserDefinedFieldSearchInstance($query_parser);
                 $udf_search->setFields(array($name));
                 $result_obj = $udf_search->performSearch();
                 // Store entries
                 $this->__storeEntries($result_obj);
                 break;
             case FIELD_TYPE_SELECT:
                 // Do a phrase query for select fields
                 $query_parser = $this->__parseQueryString('"' . $query_string . '"');
             case FIELD_TYPE_TEXT:
                 $user_search =& ilObjectSearchFactory::_getUserSearchInstance($query_parser);
                 $user_search->setFields(array($name));
                 $result_obj = $user_search->performSearch();
                 // store entries
                 $this->__storeEntries($result_obj);
                 break;
         }
     }
 }