隔行如隔山
gé háng rú gé shāngehangrugeshan
- different trades, worlds apart (idiom); to sb outside the profession, it is a closed book
gé háng rú gé shāngehangrugeshan
Data from JMdict, KANJIDIC2 (EDRDG), KanjiVG, CC-CEDICT and Make Me a Hanzi. Sources and licences