Firstly, Buddhism teaches two types of truth — relative truth and ultimate truth. The word "truth" is used in both cases to indicate they are both real.

What is real? As an example, all the appearances in a dream are not real to a person who is awake; however, they are very real to a person in the midst of a dream, just as the experiences in life are very real to a person during the day. Similarly, a practitioner and a non-practitioner see this world differently. However, each thinks the world he or she lives in is real.

~ Depicted from ARE U READY FOR HAPPINESS : The Significance of Buddhist Philosophy Today