Why doesn't the tag group search return matching products?

I’m using the Tag Group system that has been suggested a lot throughout the forums to build a filtering system. That’s all fine. TagGroup:TagValue etc.

The issue I am having is when it comes to search. If I had a product with the tag Region:Abruzzo then when I said for ‘Abruzzo’ I would expect the product to return? But it doesn’t? Surely it should be matching products that match any part of the tag?

Does anyone know why?

Just updating this post.

If I change a tag group from using semi-colons to, for example, using another separator @, the product is returned.

Before:
Product has tag Region:Abruzzo
Search for ‘Abruzzo’
No product returned

After:
Product has tag Region@Abruzzo
Search for ‘Abruzzo’
Product is returned

Any thoughts?