potency vs string to one's bow

potency

noun
  • The ability or capacity to perform something 

  • Concentration; strength 

  • Sexual virility: the ability to become erect or achieve orgasm. 

  • Potentiality, ability, capacity. 

  • Power, authority. 

string to one's bow

noun
  • A skill, ability or resource. 

  • A lover, paramour or suitor. 

How often have the words potency and string to one's bow occurred in a corpus of books? (source: Google Ngram Viewer )