title: xpath for-each multiple conditions
body: <p>What is wrong with the following line?</p>
  
  <pre><code>&lt;xsl:for-each select="//Node1/Node2/Node3 [.!='Primary' or .!='Secondary' ]"&gt;
  </code></pre>
  
  <p>Trying to select all elements where Node3 is not Primary o Secondary.</p>
  
  <p>Thanks.</p>