Tag to show Related Content Type and Term
You could create two separate vocabularies each with the same terms in it, then make one vocabulary available to content A and the other vocabulary available to content B.

An alternative is to use views: https://drupal.org/project/views

With Views you can list items of a Content type with certain tags associated with it on a page.

E.g. I have two content types News &amp; events both are categorized by term group. I only want display all News items so I use Views to only show content type News.