Missing search result for exact article name, unless "title:" operator is used

[mvuets]

I was trying to check if this article Files are hard had been submitted before, but search gave me zero results. I'd expect one-to-one match should be included. The article does show up when "title:" operator is used, though:

• Files are hard

  0 results for Files are hard
  Search query parsed to:
  Files
      Term: Files 
  are
      Term: are 
  hard
      Term: hard
  

• title:"Files are hard"

  1 result for title:"Files are hard"
  
  Search query parsed to:
  
  title:"Files are hard"
      Title: "Files are hard"