How to control which ads shows up in a specific post

Ok so I create a bunch of ads using your plugin... but I don't see any way to ensure that only my reputation marketing ads show up on my posts that talk about reputation..

I don't want an ad for something other than reputation coming up on those posts.. that wouldn't make sense.. "hey check out facebook marketing"..

So how to I use categories, and isolate which ads show up on specific posts?