Bi Xenon HID bulb on an 04 Nissan Xterra?

Can a Bi Xenon HID bulb be used on an 04 xterra? Someone told me I needed to have a separate bulb for the high and low beam lights. But several websites offer bi xenons for 04 xterras. Also, a friend of mine said that he had separate bulbs for high and low beams on his car, but he replaced them with a bi xenon bulb and it works fine