Exclude image url from search query

try this to exclude images from search. Add code to your functions.php:

// Exclude images from search results - WordPress
add_action( 'init', 'exclude_images_from_search_results' );
function exclude_images_from_search_results() {
 global $wp_post_types;

 $wp_post_types['attachment']->exclude_from_search = true;
}