title: How to return string count in multiple files in Linux
body: <p>I have multiple xml files and I want to count some string in it.
  How to return string count with files names in Linux?
  The string I want to count InvoıceNo:
  Result will be;</p>
  
  <pre><code>       test.xml InvoiceCount:2
         test1.xml InvoiceCount:5
         test2.xml InvoiceCount:10
  </code></pre>