You don’t need to use all seduction skills to get to the H scene with any girl during a seduction encounter. If she’s running away on her own, this means you didn’t impress her/score enough seduction points. Did you check out the tutorial? It covers this too.
To get an H scene, you need to score seduction points by using the correct skills to please the girl. You’ll see if you are using the right one if a big heart will pop up. Once she’s impressed enough, she will finish the seduction encounter, and you will choose an H scene. Just do your best at scoring seduction points and that’s about it.