This is the 51st most frequent Turkish word.
bazı
"Some" or "a few."
Here, 'bazı' signifies 'some' specific days, still indefinite, demonstrating a subset of the concept 'days'.
Bazı günlerde hava çok güzel oluyor.
Some days, the weather is very nice.
In this usage, 'bazı' points to an undefined selection of 'books', emphasizing an unbounded countable subset.
Bazı kitapları okumaktan çok keyif alıyorum.
I enjoy reading some books a lot.
In this sentence, 'bazı' means 'some' and indicates an indefinite quantity referring to an unspecified group of 'people'.