Larian Studios Forums Divinity - Original Sin Divinity - Original Sin - General Chain Lightning skillbook at vendor?

The game will only show you skill books within a range of the character's level. If that's the case, how are you savescumming for the vendor?

The vendor refreshes inventory when your main characters level up, so you'd have to, say, save before getting a quest reward that levels you up and then get the reward and check the vendor for reach reload.

If that's what you are doing and you still aren't having any luck... make sure you check vendors other than Cylia? Depending on where you are in the game a few vendors sell random skill books as well.