clickable filterresults

About this page, https://test.imzaadex.com/product/astrophytum-asterias-hybrid/
Why are 2 filter results clickable (astrophytum and yellow red) while the other two (green and global) are not?
I checked settings but cannot find any differences. Also, there are more products with all filters.

This is the previous page: https://test.imzaadex.com/product-category/cacti/

The page I need help with: [log in to see the link]