I currently have McAfee AntVirus Plus full version on my PC, but the virus (trojan) still can infected my PC. I was scan my pc many time, and the program is update, but i still can find virus in my PC
You can find many useful suggestions in to rid your computer of the virus. Getsusp is an excellent program as well as Malwarebytes (free version)
What makes you think you have an undetected virus?