When you mess around with something, this means that you do something or use something in a playful way, maybe in a way that you're not supposed to be doing it, depending on the situation.

当你“瞎摆弄” 某物时，这你以一种玩乐的方式去事或使用某物，可能是在一种你不该这样的情况下，体视情境而定。

I was just playing around, you know, fiddling around in the choir room, just doing normal little kid stuff.

我只是随便玩玩， 你知道的，在合唱室里瞎摆弄， 通小孩的日常小事情。

All I see is a boy meddling with things he doesn't understand.

‎我只看见一个毛头小子 ‎在瞎摆弄他不懂的东西。