SEARCH EXCEPTION

Apache_Solr_HttpTransportException: '400' Status: Bad Request in /var/www/searchAssistant/Apache/Solr/Service.php:338
Stack trace:
#0 /var/www/searchAssistant/Apache/Solr/Service.php(1170): Apache_Solr_Service->_sendRawGet('http://172.20.2...')
#1 /var/www/searchAssistant/document.php(109): Apache_Solr_Service->search('parent_id:{{ref...', 0, 3200, Array)
#2 {main}

Full Query parent_id:{{reference}} Pos =