public function searchUserGroups($name, $parentLocationId = null)
    {
        $criterionArray = array(
            new Criterion\Subtree(self::USERGROUP_ROOT_SUBTREE),
            new Criterion\ContentTypeIdentifier(self::USERGROUP_CONTENT_IDENTIFIER),
            new Criterion\Field('name', Criterion\Operator::EQ, $name),
        );
        if ($parentLocationId) {
            $criterionArray[] = new Criterion\ParentLocationId($parentLocationId);
        }
        $query = new Query();
        $query->filter = new Criterion\LogicalAnd($criterionArray);

        $result = $this->searchService->findContent($query, array(), false);

        return $result->searchHits;
    }