"Hello, I am Clef, Guru of Ceiphro and Ascended of Naut. I do not suppose that there is a lexicon or list that you are aware of that I can use to research topics that have available books, rather than guessing based upon keywords? It would be advantageous to everyone on the train if we had some proper idea of what we are actually purchasing."

[A beat.]

[Oh. Right. Manners.]

"Thank you."