zhēn rén bù lòu xiàng, lòu xiàng fēi zhēn rén
真 人 不 露 相， 露 相 非 真 人

A wise head makes a close mouth.

解释 ( paraphrase )
指得道的人不以形相现于人前。借喻不在人前露脸或暴露身分。
这条谚语强调谦虚是难能可贵的美德，保持低调而不吹嘘炫耀的作风会有助于成功的人更上一层楼；而倾向暴露自己身份或成果的人就会处于被动的地位，很难再取得进步。

This proverb tells us that a truly talented individual does not vie for attention by showing off his skills, while a person pretending to show off his exquisite skills is not so talented in fact and may ruin his previous efforts.
The proverb emphasizes that modesty is a kind of virtue. Keeping a low file and avoiding self-praise will help a successful man make further progress; however, a person keen on revealing achievement will be passive and find difficulty in improving.

真人：道教指修行得道的人。
         True man (i.e. a man who has attained enlightenment or immortality; used esp. in official Taoist titles)

露相：露出真实面目。
         Reveal oneself as one really is.

同义词 ( synonym )
深藏不露

造句 ( example )
我经常在校园里看到一个低头走路的老头，原来竟是我们学校的教授，真是“真人不露相，露相非真人”啊。