Be like looking/searching for a needle in a haystack 如同大海捞针

like 像

look for/search for 寻找

needle 针

haystack 干草堆

There’re like, thousands of files piled up,it’ll be like looking for a needle in a haystack.有成千上万份文件堆在一起，这将如同大海捞针。

The police told her that searching for the dog was like looking for a needle in a haystack.警察告诉她寻找这条狗就像大海捞针。

It soon became clear that we were looking for a needle in a haystack. 很快我们发现，我们就是在大海捞针。