to change something slightly, especially in order to make it more correct, effective, or suitable

The software is pretty much there - it just needs a little tweaking. 软件差不多好了——只需要一点点改进。

You just need to tweak the last paragraph and then it's done. 你只需要把最后一段稍作修改就可以了。

to pull and twist something with a small sudden movement

Standing in front of the mirror she tweaked a strand of hair into place. 她站在镜子前，把一缕头发捋好。