Joey Tribbiani, a character from the TV show "Friends," is known for his love of entertainment and not being the most intellectually inclined. In the episode titled "The One with the Embryos" (Season 4, Episode 12), Joey buys a volume of the encyclopedia set from a salesman. However, the specific volume that he purchases is not mentioned in the episode. The focus of the episode is primarily on the trivia game between the friends, where Joey's lack of knowledge becomes a humorous element.