Hi there!

It seems like you’ve solved this issue? I visited the page you linked to, selected several options and clicked the filter button, which resulted in filtered results, as expected:

If you require further assistance, please provide more info and include steps for how to recreate the issue. It might also be worthwhile to swap out your theme to a standard one like Storefront Theme, to determine if the issue is theme-specific or not.

You could take it a step further and do the same with your plugins. Do a non-invasive conflict test that won’t disrupt your site, and will be visible to you only (your site visitors will not experience anything different). Start by installing and activating the Health Check & Troubleshooting plugin, and then follow this guide:
https://docs.woocommerce.com/document/configuring-caching-plugins/