ON September 10, 2002 Mary He was thirty thousand meters above the Pacific Ocean, en route from Vancouver to Beijing. But the Chinese capital was not her final destination.Chinese-born Mary He, who now lives in Canada, took a 4-hour connecting flight to Urumqi, and then another 2-hour flight to Kashi in western China's Xinjiang Uygur Autonomous Region. She spent the third day of her journey on a coach, traveling for more than 10 hours across the Gobi desertto Hotan. There, she continued her 30-year search for a Uygur boy named Ircken.