by oneself vs conjointly

by oneself

adv
  • without outside assistance 

prep
  • Alone; without assistance or help from others. 

  • Alone, without another's immediate company 

  • Used other than figuratively or idiomatically: see by, oneself. 

conjointly

adv
  • In a conjoint manner; jointly or together 

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