Conventual vs Spiritual

Conventual

noun
  • A member of one of the two divisions of the Franciscans, following a mitigated rule, the other being the Observants. 

Spiritual

noun
  • A member of a branch of the Franciscan order that advocated simple dress and renounced the owning of property. 

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