Is it true that criminal laws deals with people who have been accused of acts that harm society

Generally, I would say yes to this question.

We may want to nuance the thought a bit, however.  Criminal law defines what acts constitute crimes, and those who commit crimes are prosecuted and punished under criminal law.  Do all crimes hurt society?  In a sense, yes.  But even a crime that has just one victim and isn't much noticed in the wider spectrum of society still is a crime subject to arrest and prosecution under criminal law.