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 );
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 );