知人知面不知心 (zi1 jan4 zi1 min6 bat1 zi1 sam1) — you may know a person's face, yet you don't no his or her heart; it's hard to know sb. true nature [also] [粵]人心隔肚皮 ; 知人口面不知心 in Cantonese
ziˉ¹知janˎ₄人ziˉ¹知minˍ₆面batˉ¹不ziˉ¹知samˉ¹心Mandarin Pinyin: zhi1 ren2 zhi1 mian4 bu4 zhi1 xin1
Meaning of 知人知面不知心
nounyou may know a person's face, yet you don't no his or her heart; it's hard to know sb. true nature [also] [粵]人心隔肚皮 ; 知人口面不知心