Never buy a pig in a poke .

不要隔着口袋买小猪。（喻未见真货，不要瞎买）

youdao

Never buy a pig in a poke.

千万别买袋子里的猪。

youdao

I want to see the tennis racket before I agree to the price. I don't want to buy a pig in a poke.

我想先看看网球拍然后才能接受这个价位，我可不想胡乱买东西。

youdao

I'm not going to buy a pig in a poke.

CNN: Issa: Holder must turn over documents or face contempt vote