The term "beeswax" in this context has no actual connection to beeswax from bees' nests. Instead, it represents a matter or affair in a somewhat humorous or folksy way, particularly someone else's affairs.
Here's an example of how the phrase "mind your own beeswax" could be used in a conversation:
* Person A: "Why is John not talking to Mary these days?"
* Person B: "Oh, just let them be. It's their business; mind your own beeswax."
This response from Person B suggests that they want Person A to stay out of the matter between John and Mary and focus on their own concerns instead.