I'd like to buy bitcoins quickly with my credit card
please suggest a good service without verification process and low fees
You simply can't get "without verification" and "low fees" in the same sentence.
Otherwise, the exchange will be faced with huge amounts of fraudulent exchange activity which they won't even get rewarded on. It's simply not a sustainable business model for them.
I'd say that if you truly want to buy BTC without any form of verification, the best rates that you're going to get is Virwox rates/Localbitcoins/Paxful/xcoins. Compare the rates but generally you'll find them to be pretty steep in terms of fees. Other than that I honestly don't think you can do much more given the prerequisite of no verification.