He knew the ladies on the bed, and he knew the shoes on the bed. What does it mean?

This is a popular saying in Guo Degang's crosstalk. It means that someone is very familiar with family and social situations but not very familiar with certain aspects such as going to bed and going down the stairs. On the contrary, someone might know something very well but not very familiar with it, such as shoes. This sentence expressed a kind of teasing and humorous mood.