人不知，鬼不觉

Explanation: Describe things done very secretly, without being noticed. 　　Usage: Complex sentence; for clause; with compliment 　　Source: Yuan Anonymous "enemy creditors" second off: "This worries of God without our noticing, days high, come thick." Thesaurus:  Unconsciously, spirit guiltless, ghost cannot help, Did not know I do not know, dottiness