I worked 40hours paid for 40hours but
Pay check stub says work 32hours and
8hours for holiday pay which is I don't get holiday pay,
What is the reason for it?
Any idea?

Thank you

Ask your payroll department. Was there a holiday during the pay period?

Yes, there is one but I did not work on that day and I know that
If I don't work I don't get holiday pay

Are you sure about that? Generally, if you are scheduled to work on a holiday you get paid for the day.

I wasn't scheduled to work, and I didn't.
My question is the pay stub that is saying
32hours work time insteed of 40hours that I worked,
And put 8hours holiday pay which is my total
Pay are same, comepany think look nice on my
Pay stub? Or any tax reason?

Again, have you asked your payroll or HR department? It could just be a clerical error. There is no advantage to the company or you classifying the pay that way.