title: grep for string in all files in directories with certain names
body: <p>I have csv files in directories with this structure:</p>
  
  <pre><code>20090120/
  20090121/
  20090122/
  etc...
  </code></pre>
  
  <p>I want to grep for a certain string in all of the csv files in these directories, but only for January 2009, e.g. 200901*/*.csv</p>
  
  <p>Is there a bash command line argument that can do this?</p>