挖空心思

wākōngxīnsī
  1. (usually derogatory) to rack one's brains; to search everything for an answer
  2. to rack one's brains; to search everything for an answer

Wiktionary

Homographs

挖空心思 wākōngxīnsi
  1. to dig for thoughts (idiom); to search everything for an answer
  2. to rack one's brains

Entry Composition

1 挖空 wākōng
  1. to excavate
  2. to hollow
=2 心思 xīnsi
  1. mind
  2. thoughts
  3. inclination
  4. mood
=2 心思 xīnsī
  1. feeling; mood; emotions; state of mind
  2. intentions; plans
  3. thinking
  4. thoughts; ideas