别疑神疑鬼
a grain of salt：一撮盐；半信半疑
I took the news with a grain of salt.
我对这个消息半信半疑.
You must take all he says with a grain of salt.
凡是他说的话你都打个折扣.
Look at other applications with a grain of salt.
鸡蛋里挑骨头的眼光看待其他软件.