"mung4 gei2 sung1 gei2"

[mindy]

Hi I wanted to see if anyone knew this idiom "mung4 gei2 sung1 gei2"? It means something like you can't do anything right, like you're loose and lax at the things you do, so in a way it means you're uncapable. Unless it just means being loose? Or at least that's what I think. I'm not sure on the definition or the hanzi, so any help would be appreciated on this idiom ""mung4 gei2 sung1 gei2".

Thanks.
-Mindy

[Terence]

I can only think of 矇矇忪忪, mung1 mung1 sung1 sung1 sight not ckear juct like you just waken up.