Meaning of “dip into sth” - Learner’s Dictionary

dip into sth

phrasal verb with dip uk us /dɪp/ verb (present participle dipping, past tense and past participle dipped)
READ UK

to read small parts of a book or magazine:

It's the sort of book you can dip into now and then.
SPEND

to spend part of a supply of money that you have been keeping:

I had to dip into my savings to pay for the repairs.

(Definition of “dip into sth” from the Cambridge Learner’s Dictionary © Cambridge University Press)