why we see in every alternate mock, question based on truth and lie, is it because team cracku thinks that this there may be a question on that, or there is some other reason

Not just that...Other topics are being repeated as well.. like Codes, Coin picking games etc...Repeating types are not too great in my opinion...But considering the size of the team and the charge for the mocks I'm satisfied with it.

So what do you expect? In total of15 dashcats you want 15*5 =75 new concepts in total or what.. Even CAT paper setter can't think of that many sets.....