title: Multiple words in any order using regex
body: <p>As the title says , I need to find two specific words in a sentence. But they can be in any order and any casing. How do I go about doing this using regex?</p>
  
  <p>For example, I need to extract the words <code>test</code> and <code>long</code> from the following sentence whether the word <code>test</code> comes first or <code>long</code> comes. </p>
  
  <pre><code>This is a very long sentence used as a test
  </code></pre>
  
  <p>UPDATE:
  What I did not mention in the first part is that it needs to be case insensitive as well.</p>