however vs if only

however

conj
  • But, yet, though, although. 

  • In any way in which. 

  • Regardless of the way in which. 

adv
  • How ever: an emphatic form of how, used to ask in what manner. 

  • In contrast. 

  • To whatever degree or extent. 

  • Nevertheless; yet, still; in spite of that. 

  • In any way that one likes or chooses; in a haphazard or spontaneous way. 

if only

conj
  • Even if for no other reason than; only just. 

  • Used other than figuratively or idiomatically: see if, only. 

  • I wish that; signifies a wish or desire for the present or the future. 

  • I wish that; signifies a regret about an action in the past. 

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