75 
With the snippet below, and if I had “Puma” saved in the “_brand” custom field for some products, this search result would actually return those products!
The default WooCommerce frontend product search returns results based on whether the search term is present in the product title, SKU, short and long description.
But what if you also want to search inside a custom field i.e. you have a custom field called “_brand” and you also want to search by “_brand”?
Now, I’m not sure I’ve explained this in plain English, so let’s take a look at a practical example. Enjoy!
PHP Snippet: Search Products By Custom Field Value @ WooCommerce Search
The only thing you need to change in the snippet below is ‘_brand‘. Change it to the key of your custom field, and you should get results based on that. Let me know in the comments if it works!
/**
* @snippet Search By Custom Field @ WooCommerce Search
* @how-to Get tutoraspire.com FREE
* @author Tutor Aspire
* @compatible WooCommerce 6
* @donate $9 https://www.tutoraspire.com
*/
add_filter( 'posts_search', 'tutoraspire_product_search_by_custom_field' );
function tutoraspire_product_search_by_custom_field( $where ) {
global $wpdb, $wp;
if ( is_admin() || ! is_search() || ! isset( $wp->query_vars['s'] ) || 'product' != $wp->query_vars['post_type'] ) {
return $where;
}
$product_ids = array();
$terms = explode( ',', $wp->query_vars['s'] );
foreach ( $terms as $term ) {
$products = $wpdb->get_results( $wpdb->prepare( "SELECT ID, post_parent FROM {$wpdb->posts} LEFT JOIN {$wpdb->postmeta} ON {$wpdb->posts}.ID = {$wpdb->postmeta}.post_id WHERE meta_key IN ( '_brand' ) AND meta_value LIKE %s;", '%' . $wpdb->esc_like( wc_clean( $term ) ) . '%' ) );
$products = array_merge( wp_list_pluck( $products, 'ID' ), wp_list_pluck( $products, 'post_parent' ) );
if ( sizeof( $products ) > 0 ) {
$product_ids = array_merge( $product_ids, $products );
}
}
$product_ids = array_filter( array_unique( array_map( 'absint', $product_ids ) ) );
if ( sizeof( $product_ids ) > 0 ) {
$where = str_replace( 'AND (((', "AND ( ({$wpdb->posts}.ID IN (" . implode( ',', $product_ids ) . ")) OR ((", $where );
}
return $where;
}