не быть уверенным

From LSJ

ὀδοῦσι καὶ ὄνυξι καὶ πάσῃ μηχανῇ → tooth and nail | tooth, fang, and claw | in every possible way | by hook or by crook

Source

Russian > Greek

ἀγνοέω, ἀγνοιέω