doo-doo vs guano

doo-doo

noun

  • Excrement. 

  • Difficulty; trouble. 

guano

noun

  • Coccothrinax borhidiana, a variety of palm tree indigenous to Cuba. 

  • Dung from a sea bird or from a bat. 

How often have the words doo-doo and guano occurred in a corpus of books? (source: Google Ngram Viewer )