When you accept this quest you are given the skills Resurrect and Retribution. Head north, towards Tomaat Pass and look for a Nong Berry Bush. Beware of a nearby Red Yeti. After picking up the berries from that bush, head farther north, to the Seijun Woods and look for a Tai Ling Vine and pick the buds. After you have them both return to Brother Pe Wan to complete the quest.