breathing space vs breathing spell

breathing space

noun
  • A rest, pause, or respite. 

  • Enough distance so that one can feel unfettered. 

  • Sufficient space or a span of time in which to recover one's breath. 

breathing spell

noun
  • An opportunity to rest or give thought to a situation; a short respite. 

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