Where should I go to improve my midgame?

I feel like I end up in the same position often. I'm a decent enough player overall, with some opening knowledge and probably strongest in the end game. But time after time I get to a position like this amd I just don't know how to advance. It's not about finding a good move it's that I just have no strategy I can see so end up pushing pieces in the blind hope something will happen.

Here's a typical example. Queen Gambit accepted as black, navigate the counter play, get pieces to decent squares and then... a lull. No immediate pressure on me so it feels like I should up the tempo and attack. But I have no idea how to attack or how to learn how to come up with a strategy. Do I need lessons from a better player or are there online resources? Amd if I do need lessons how to pick the right coach?

Thanks in advance!

In this position you're a pawn up, also you have a nice majority on the queenside which you can easily push forward.

Pushing queen side majority looks good