Before creating own product attributes,make sure that terms titles don’t contain white spaces otherwise you’ll always have invalid result while product filtration.There 2 ways how this problem can be solved:
1.Use “-“(dash symbol) between words in terms titles like in example below;
2.Just follow wp-content/themes/brideliness/woocommerce/content-product.php file straight on your server and replace “names” with “slugs” (string:35)
and you’ll be able to use white spaces in terms titles.