clean language vs impiety

clean language

noun
  • A questioning technique focused on the use of language, assumptions, metaphors, paradigms and sensations familiar to the person questioned. 

impiety

noun
  • The lack of respect for a god or something sacred. 

  • An impious act. 

  • The state of being impious. 

How often have the words clean language and impiety occurred in a corpus of books? (source: Google Ngram Viewer )