Change Default No Media Found Message in Media Tab

You can use this filter rtmedia_no_media_found_message_filter in your theme and can modify the default message of  “Oops ! There’s no media found for the request !!”

In your current theme’s functions.php file, use below code:

function custom_no_media_found_message_function( $message ) {
$message = "Custom Message Comes Here ... !";
return $message;
}
add_filter( 'rtmedia_no_media_found_message_filter', 'custom_no_media_found_message_function' ,10, 1 ); 

Result will be like below:

 

Note: Make sure to change the custom message as per your need.