I have used Amazon to order books. You can select the type of shipping you want to use. The faster the shipping the more it costs. I used the budget shipping or cheapest shipping. My books came in a couple of weeks. I hope this answers your question. If not, then please reply. Thank you.
My question is specific , Does it take exactly like what they wrote 4-8 days or may it takes more ?
I think my books took less time. That may not indicate that your books would come in less time. You could email Amazon to ask.