A secret door in the archive on the island of the blood moon (Divinity: Original Sin 2)

Good day, comrades. Can't find the secret door in the archive. In all passages it is written that you just get to the secret door between the shelves. FEIN trying to find the intelligence he's 30, did up to 40, it does not find, and through the stone arch between cabinets to go also cannot. What to do?