Bootleg PS2 Game Question

I got this ps2 game GTA Vice City and other ps2 game I got for no more then 1 dollar in South America when I went for vacation. I got these game that got the case and everything you see on the original except the CD don't look the same because is a bootleg.Mine games doesn't work on my Ps2 but people told me that it work normal but in the U.S where I live it doesn't work for me.

I heard someone in this forum who I don't remember who it was say something about people doing something to make the bootleg game work for ps2 but that all I remember.

So if anyone else here who can help me by giving me advice or anything I would appreciate because I got a lot of good game for cheap that I want to play lol.

.1

My Only Suggestion is a Mod Chip

Yep.
Or u can get Swap Magic. Google it.

Thank a lot