хорошо укрытый

From LSJ

οὐκ ἐν τῷ πολλῷ τὸ εὖ, ἀλλ' ἐν τῷ εὖ τὸ πολύgood is not found in plenty but plenty in good, quality matters more than quantity

Source

Russian > Greek

εὐφύλακτος, δυσεπιβούλευτος