title: How to find all occurrences of a variable in Vim?
body: <p>In vim, how to I find all occurrences of a variable in files under a certain directory?</p>
  
  <p>I know vimgrep works sometimes, but it looks for text only and doesn't work if other classes have variables of the same name and I only want the variable under a specific class.</p>
  
  <p>What should I do? Or should I get an IDE instead?</p>