Robert Thurman, whose erudite, exuberant efforts to expand the West’s understanding of Tibetan Buddhism earned him a reputation as “the Dalai Lama’s man in America,” died on Tuesday at his home in Woodstock, N.Y. He was 84. 因学识渊博、热情洋溢地致力于增进西方对藏传佛教的理解，罗伯特…