if( ! function_exists( 'filter_the_main_video_args' ) ){
    /**
     *
     * Filter the main video args
     *
     * @param unknown $query_args
     * @param unknown $widget_id
     */
    function filter_the_main_video_args( $query_args, $widget_id ) {
        // Do not query these tag videos
        $query_args['tax_query'][] = array(
            'taxonomy' => 'video_tag',
            'field'    => 'slug',
            'terms'    => array( 'tag_1', 'tag_2', 'tag_3' ),// or array( 'tag_1' )
            'operator' => 'NOT IN'
        );
        return $query_args;
    }
    add_filter( 'mars_main_widget_args' , 'filter_the_main_video_args', 10, 2 );
}