Subcategory Issues

I have two main categories (versions of our software) ie7.0 and 6.05.

Underneath them they will have very similar articles but some changes between them due to different versions.

So each main category has a sub category.

Console
Winops
Rep Dashboard

When I click on v6.06 it only shows articles associated underneath and does not show the subcategories how do I get the subcategories to show?

https://wordpress.org/plugins/wp-knowledgebase/