Exclude downloads from showing in search results
<?php
/*
 * Plugin Name: Easy Digital Downloads - Exclude downloads from search
 * Description: Exclude downloads from showing in search results
 * Author: Easy Digital Downloads
 * Author URI: https://easydigitaldownloads.com/
 * Version: 1.0
 */

function sumobi_download_post_type_args( $download_args ) {
	$download_args['exclude_from_search'] = true;

	return $download_args;
}
add_filter( 'edd_download_post_type_args', 'sumobi_download_post_type_args' );
To implement this snippet on your site, create a brand new, empty WordPress plugin and paste the above code inside.