How to Use Amazon's Keyword Search to Sell Books

Within Amazon then, I have kind of have for now, I have two options. The product display ads and the keyword search ads. They're now called lock screen ads. So you can't use product display ads through the KDP version. You can use them through advantage. What is the most effect, like if, if you were starting out now, which one would you focus on? Definitely sponsored keyword ads. Lock screen ads are tough to make work effectively for lots of different reasons.