The bottom of this sentence is "fly first like a stupid bird"
What car has no wheels: (like) refers to a car in chess. The so-called car has no wheels, and the horse has no rein.
What pig has no mouth: (only) Tongzhi, the ancients thought that spiders had no mouth,
What donkey has no hair: (stupid) stupid donkey refers to swearing, and here only donkey has hair, which is the meaning of this word.
There is no door in any house: the bird's nest has no door because it faces the sky.
What book has no words: (1) Here, the book means writing, but of course there is no words before writing.
What flower has no leaves: (Flying flower) Flying flower has fallen leaves, so flying flower has no leaves.