買櫝還珠 [买椟还－]

Jyutping maai5 duk6 waan4 zyu1
Pinyin mǎi dú huán zhū

Definitions (CC-CEDICT)
  1. to buy a wooden box and return the pearls inside
  2. to show poor judgment (idiom)
Definitions (Wiktionary)
  1. phrase, figuratively, idiomatic
    to show poor judgement
Definitions (Kaifangcidian)
  1. （沒有對應漢語詞彙）