add_filter( 'wpv_filter_taxonomy_frontend_search_get_terms_args', 'prefix_modify_get_terms_args', 10, 3 );
  
function prefix_modify_get_terms_args( $args, $taxonomy, $view_id ) {
    if ( $view_id == 1223 && $taxonomy == "topic") {
        $args['parent'] = 0;
    }
    return $args;
}

add_filter( 'wpv_filter_taxonomy_query', 'prefix_modify_taxonomy_view_args', 99, 3 );
function prefix_modify_taxonomy_view_args( $tax_args, $view_settings, $view_id ) {
    if ( $view_id == 1201 ) {
        $tax_args['parent'] == 0;
    }
    return $tax_args
}