Hello again Danil!
You are right, there are no books mentioned for those subjects because they don’t require books. All materials you need for those subjects (so, Finance & Accounting, Identity Development, etc.) will be either downloadable, given to you in class or something like that and no physical books have to be purchased other than those on StudyStore. That is the website Saxion refers to itself, too. If a teacher wants to recommend a book at a later stage they can, however, you definitely do not have to buy more than those mentioned on StudyStore to begin with.
So, don’t worry about that, you’ll be fine with those mentioned :)