ㄉㄢdānㄐㄧㄥjīngㄐㄧㄝˊjiéㄌㄩˋ

  1. 竭盡精力思慮清史稿··儒林·》:大毛言簡意賅殫精竭慮專攻。」殫心竭慮」、殫思極慮」。殫智竭力殫思極慮竭盡心思掉以輕心

to exhaust one's thoughts and ingenuity (idiom)​; to think sth through thoroughly, to rack one's brains, to leave no stone unturned
concentrer toute son attention, déployer toutes les forces de son esprit
sich den Kopf zerbrechen (S)​