ㄇㄨˋㄅㄨˋㄎㄨㄟㄩㄢˊmùbùkuīyuán

目不窥园
  1. 形容專心苦學 念書潛心鑽研目不窺園」。

lit. not even peek at the garden, fig. to be absorbed in one's studies (idiom)​