global query

// WP_Query arguments
$args = array(
	'post_type'              => array( 'question' ),
	's'                      => 'skype',
	'tax_query'              => array(
		'relation' => 'OR',
		array(
			'taxonomy'         => 'post_tag',
			'terms'            => 'skype',
			'field'            => 'name',
		),
	),
);

// The Query
$query = new WP_Query( $args );