ㄒㄧㄣㄐㄧㄝˊxīnjié

心结
  1. 存在難以紓解抑鬱想法 解開心結」、心結」。

a matter that gnaws at one's mind, preoccupation, sore point, rancor
Herzensangelegenheit, Herzenssache, emotionales Problem (S, Psych)​