徽墨
Anhui ink (known for its quality)
濊貊
Yemaek, ancient ethnic group of Manchuria and Korea, precursors of Korean Goguryeo kingdom
讳莫如深
important matter that must be kept secret (idiom); don't breathe a word of it to anyone!
后悔莫及
too late for regrets (idiom); It is useless to repent after the event.
追悔莫及
too late for regrets (idiom); It is useless to repent after the event.