Pore over. Pored over. (Avoid pouring over books, fluid irregardless).
Possibly among the best, but not so 'euphonic' is "Reading for detail ..." - A possibly unfamiliar but well used term. eg
Answers - What is reading for detail?
- Reading for detail can mean that when you read you pay very close attention to each and every detail in the reading such as dates, quantities, and names.
One stop English
- Skills: Reading skills include reading for gist, reading for detail. There are also speaking activities and opportunities for writing practice.
Improve reading skills
- ... Extensive reading - used for pleasure and general understanding Intensive reading - accurate reading for detail*ed* understanding.
Also and here
NGram. "Reading for detail", with "a dark and stormy night" for frequency of use comparison.