title: XmlNode.SelectNode with multiple attribute
body: <p>One of my nodes inmy xml file is as follows.</p>
  
  <pre><code>  &lt;LOGIN_ID NAME="Kapil"&gt;
      &lt;SEARCH_ID&gt;Kapil Koli&lt;/SEARCH_ID&gt;
      &lt;GUID&gt;111&lt;/GUID&gt;
      &lt;FIRST_NAME&gt;Kapil&lt;/FIRST_NAME&gt;
      &lt;LAST_NAME&gt;Koli&lt;/LAST_NAME&gt;
      &lt;EMAIL_ID&gt;kapil@abc.co.in&lt;/EMAIL_ID&gt;
      &lt;PASSWORD&gt;abc123**&lt;/PASSWORD&gt;
    &lt;/LOGIN_ID&gt;
  </code></pre>
  
  <p>The code I am using is - </p>
  
  <pre><code>XmlDocument document = new XmlDocument();
  document.Load(_XmlFileName);
  nodeList = document.SelectNode."USERS/LOGIN_ID[contains(SEARCH_ID,'Kapil')";
  nodeList = document.SelectNode."USERS/LOGIN_ID[contains(EMAIL_ID,'kapil@abc.co.in')";
  </code></pre>
  
  <p>I want to use select node which will accept search_id and login_id as attributes to search?
  If either search_id or email_id is wrong, I want to return null.
  How could I do this?</p>
  
  <p>thanks.
  kapil.</p>