How did Shakespeare subtly make his comedies profound?

It is a common practice in Shakespeare's plays to skillfully integrate the most interesting and dramatic folk stories into the drama, making it natural with the whole plot. For example, in the love between Bassanio and Bohemia, the courtship story from three boxes of gold, silver and lead was incorporated, named after the smart and beautiful Bohemia. Examples hidden in unpretentious lead bottles show that true love does not necessarily have a gorgeous appearance. In addition to the main story line, there are some double lines. For example, Shylock's own daughter fell in love with Lorenzo, a Christian youth, and they eloped resolutely to avoid her father's obstruction. The addition of these reasonable ingredients makes a hilarious comedy contain rich and profound contents.