Related products not working

Hi

I can not find a way to get related products working on our website.

https://onlineworktops.co.uk/product/aria-black-granite-12mm-compact-laminate

We want related products to be based on the title or tags in the page a customer is on. However it keeps showing the same unrelated products on the page. Any help would be appreciated.

Thanks

Nathan

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