內行看門道，外行看熱鬧 [内－－门－－－－－热闹]

Jyutping noi6 hong4 hon3 mun4 dou6 , ngoi6 hong4 hon3 jit6 naau6
Pinyin nèi háng kàn mén dao , wài háng kàn rè nao

Definitions (CC-CEDICT)
  1. while the connoisseur recognizes the artistry, the layman simply enjoys the show