if ( $query->is_search ) {
    if ($_REQUEST['search_type'] == 'wycieczki' ) {
        $curr_month = date('m');
        $curr_year = date('Y');
        if ($_REQUEST['abc'] != "all" && isset($_REQUEST['abc'])) {

            $chosen_month = date($_REQUEST['abc']);

            if ($curr_month < $chosen_month) {
                $query_date_start = date("01"."/".$chosen_month."/".$curr_year);
                $query_date_end = date("t"."/".$chosen_month."/".$curr_year);
            }

            if ($curr_month >= $chosen_month) {
                $query_date_start = date("01"."/".$chosen_month."/".($curr_year + 1));
                $query_date_end = date("t"."/".$chosen_month."/".($curr_year + 1));
            }

            $query->set('meta_query', array(
                'relation' => 'AND',
                array(
//                'key'       => 'trip_start_date',
////                'value'     => array( $query_date_start, $query_date_end),
//                'value'     =>  $query_date_start,
//                'compare'   => '=',
//                'type'      => 'DATE''key' => 'trip_start_date',
                            'key' => 'trip_start_date',
//                            'type' => 'DATE',
                            'value' => '12',
                            'compare' => 'LIKE'
                )
                )
            );

        }
    }
//
//        $query->set('post_type', array(
//                'wycieczki'
//        ));

    }

    return $query;