Main Walkthrough

Location: Shiping Village
Petitioner: Liux Bod 
Reward: Buguzhi, Lingzhi, Begonia

The toughest part of triggering this side quest is reaching it in the first place. The petitioner, Liux Bod, lives in Shiping Village, deep within the southwestern region of Nanjiang. You won't get to visit this place until you reach the main story quest. Once you can travel through Nanjiang, head to Miasma Lurk Forest and use the northern exit. Travel west along the main map and you'll find Shiping Village, down the road from Butterfly Village.

Liux Bod is standing a short walk from the entrance to the village. Speak to him and he'll express fear for his mother, who is suffering from an illness. She needs Honey, which is found in the nearby Herb Valley - but there are too many deadly snakes in the area to safely collect any. Yi and his friends have no problem with danger.

Head west to Herb Valley. Among other things, this place is populated by Bees and Bee Swarms. Defeating either enemy has a chance of earning you some Honey. Bees and Bee Swarms are pretty common spawns, so you shouldn't have any trouble collecting Honey. 

Bring five doses of Honey to Liux Bod to complete the quest. 

If you've also completed the side quest Rotten Vines, Withered Trees, Evening Crows - this was very early in the game, way back in Wutong Village - you'll trigger a new quest, Nostalgia. Take the Begonia you received to Sun the Physician in Wutong Village and he'll give you a nice reward in return: Jinchuang Ointment, a Two-Time Refined Meridian Pill, Three-Time Refined Spirit Pills, and Martial Arts Perceptions.