string to one's bow

noun2

1. •
   A skill, ability or resource.

   • McGough has not a string to his bow. He had no friends behind him; that was the trouble. — 1932
2. •
   A lover, paramour or suitor, especially one of many.

   • Massimilla was no coquette. She had no second string to her bow, no secondo, no terzo, no patito. — 1837