diff -r 796725d33b67 -r d7c5b43d309a server/src/app/Repositories/RdfDocumentRepository.php
--- a/server/src/app/Repositories/RdfDocumentRepository.php	Wed Oct 19 13:08:02 2016 +0200
+++ b/server/src/app/Repositories/RdfDocumentRepository.php	Wed Oct 19 15:55:04 2016 +0200
@@ -159,9 +159,15 @@
             if(is_array($location)) {
                 $location = $location[0]; // we know it is not empty
             }
-            $location = $filters['location'];
             $qFilterParts[] = CorpusFilterManager::getLocationFilterPart($location);
         }
+        if(array_key_exists('themes', $filters) && !empty($filters['themes'])) {
+            $themes = $filters['themes'];
+            if(is_string($themes)) {
+                $themes = [$themes,]; // we know it is not empty
+            }
+            $qFilterParts[] = CorpusFilterManager::getThemeFilterPart($themes);
+        }
 
         $query = [
             'index' => config('corpusparole.elasticsearch_index'),