houseboy vs scullery maid

houseboy

noun
  • A non-white adult male domestic servant. 

  • A young male domestic servant, especially in a British colony in former times. 

scullery maid

noun
  • A domestic servant, of lowest status, whose job is to wash dishes and do other menial chores. 

How often have the words houseboy and scullery maid occurred in a corpus of books? (source: Google Ngram Viewer )