It means paying attention to details, but thinking that you are clear. Biography of the Book of Jin Huangfu Mi: "If it is made by the holy emperor, it is the virtue of the two emperors, and the wind is summer. I want to be warm and smooth, but I don't want to observe it. " Zhang Yungu: "Don't be confused, don't be clear, don't miss it, don't observe." Qing Wu Ren Jian's Strange Status Quo Seen in Twenty Years, p. 78.
It means to know the truth of things in the right way, but don't be too confused and arrogant.
Some people also use it to describe interpersonal communication, which is similar to the meaning of "clear water means no fish, and people have no friends."