Modifies the product description shown on WPS live search results

functions.php

add_filter( 'woocommerce_product_search_field_product_description', 'wpsrd_woocommerce_product_search_field_product_description', 10, 2 );
function wpsrd_woocommerce_product_search_field_product_description( $description, $post_id ) {
	if ( $post_id == 32 ) { // here you should use the product id you desire instead of 32
		$description = 'a description'; // write a description enclosed in single quotes 
	}
	return $description;
}