You're not following this very well. Comey said Trump was not "personally" under investigation when he was head of the FBI. The Trump Campaign was, and still is, under investigation. One has to wonder why you don't know that means if anything they find leads to Trump then he will be a target. You should also know that the Comey memos have been turned over to Mueller, that means they are looking at Trump. 

And that's really odd that you think you should have been shown some evidence by an ongoing investigation prior to that investigation completing. What makes you believe you should have seen their evidence now? And even more odd, the fact you haven't been shown evidence in an ongoing investigation leads you to conclude there is none? Are you sure that's the "logic" you want to go with?