<?php

add_action( 'pre_get_posts', 'ac_show_search_results' );

function ac_show_search_results( $query ) {

    if ( ! $query->is_page( 'some-page-slug' ) )
        return;

    $tax_query = array();

    if ( ! empty( $_GET['funeral-state'] ) ) {
        $tax_query[] = array(
            'taxonomy' => 'ac_state',
            'terms'    => $_GET['funeral-state'],
            'field'    => 'name',
        );
    }

    if ( ! empty( $_GET['funeral-city'] ) ) {
        $tax_query[] = array(
            'taxonomy' => 'ac_city',
            'terms'    => $_GET['funeral-city'],
            'field'    => 'name',
        );
    }

    if ( ! empty( $tax_query ) )
        $query->set( 'tax_query', $tax_query );

    if ( ! empty( $_GET['ac-search'] ) )
        $query->set( 's', $_GET['ac-search'] );
}