3 verses have
truthful
in Edition Clear Qur'an by Talal Itani / Yusuf (Joseph)

12:17They said, “O father, we went off racing one another, and left Joseph by our belongings; and the wolf ate him. But you will not believe us, even though we are being truthful.”

12:27But if his shirt is torn from the back: then she has lied, and he is the truthful.”

12:82“Ask the town where we were, and the caravan in which we came. We are being truthful.”