Print terms with taxonomy and metabox value

Try This:

$args = array(
    'hide_empty' => false,
    'relation' => 'OR',
          array(
            'key' => 'serial_language',
            'value' =>'english', 
            'compare' => 'LIKE'
          ),
          array(
            'key' => 'serial_language',
            'value' =>'arabic', 
            'compare' => 'LIKE'
          ),
    'taxonomy'  => 'serial',
    );
    $terms = get_terms( $args );

hope this will help