code: protected function filterSearch(PaginateFinderConfiguration $configuration, Stage $qa)
      {
          $filter = array();
          $label = $configuration->getSearchIndex('label');
          if (null !== $label && $label !== '') {
              $filter['label'] = new \MongoRegex('/.*'.$label.'.*/i');
          }
  
          $components = $configuration->getSearchIndex('components');
          if (null !== $components && is_array($components) && !empty($components)) {
              $filter['component'] =  array('$in' => $components);
          }
  
          if (!empty($filter)) {
              $qa->match($filter);
          }
  
          return $qa;
      }
docs: @param PaginateFinderConfiguration $configuration
  @param Stage                       $qa
  
  @return array