How To Trade Ancient Bone Dust With Locals For Poison Antidote?

How do I trade ancient bone dust with locals for poison antidote? My Sim has level 5 of Selvadoran Culture and tried to trade with the vendor in the marketplace or just any locals who happened to visit the bar but the interaction does not show? How do I trade ancient bone dust with locals for poison antidote? My Sims is not sick and healthy when he chatted with the vendor and the option or interaction does not appear. Before that, my Sim was so sick after being bitten by some creepy crawlies in the woods like bats, bees and spiders.