Uē hóo, uē phuê, lân uē kut, ti jîn, ti bīn, put ti sim.

華語：畫虎、畫皮、難畫骨，知人、知面、不知心。

One may know a person by his face, but can't read his mind. Don't trust people too easily. (Lit. One can draw a tiger and its skin, but it is impossible to draw its bone.)