hammer-headed vs short bus

hammer-headed

adj
  • stupid, ignorant 

  • Having a head in the shape of a hammer 

short bus

adj
  • Stupid; dumb; slow. 

noun
  • A shorter school bus, typically equipped with a wheelchair lift, used for transporting children who are physically disabled or who are being educated in special programs, often for learning disabilities. 

How often have the words hammer-headed and short bus occurred in a corpus of books? (source: Google Ngram Viewer )