bibliomancy
/ˌbɪblɪˈɒnsi/ or /ˌbɪblɪˈɒntsi/Definitions
1. noun
the practice of using books or written texts as a form of divination or fortune-telling, often by opening a book at random and interpreting the words or passages that are revealed
“The fortune teller used bibliomancy to help her client find love, by opening a romance novel and reading out the first sentence she landed on.”