[shāng nǎo jīn]
cause sb. enough headache; knotty; troublesome; bothersome
a knotty problem; headache
伤脑筋的问题
It is a nuisance the way it keeps on blowing.
风总是这么刮, 真伤脑筋。
It's rather troublesome.
这事真伤脑筋。
He puzzled his brains about the matter.
他为这些事大伤脑筋。