Getting data analytics on search keywords used to find our app

We are getting a lot of downloads via App Store search, but the application is connected to a book that you need to purchase and then use to activate the augmented reality application. We are trying to better understand where our audience are coming from and how to help them access the book and therefore be able to use the application.

Is there a way to get a report on the search terms that people who have downloaded the app are using to find our app in the App Store search? Can't see to deep dive into the source data which has come from search.