Шигаев.

add_filter('posts_search', function( $search, \WP_Query $q ) {
    if (!is_admin() && empty($search) && $q->is_search() && $q->is_main_query())
        $search .=" AND 0=1 ";

    return $search;
}, 10, 2);

function dco_navigation_markup_template() {
    return '
	<nav class="navigation %1$s" role="navigation">
		<h2 class="screen-reader-text">%2$s</h2>
		<div class="nav-links">%3$s</div>
	</nav>';
}

add_filter('navigation_markup_template', 'dco_navigation_markup_template');