title: Search windows updates with WUApiLib
body: <p>How to get only mandatory updates and optional updates by turns? In other words how do I divide into important and unimportant (optional) updates like at the picture <img src="https://i.stack.imgur.com/WigdS.png" alt="enter image description here"></p>
  
  <p>IUpdateSearcher interface has <a href="http://msdn.microsoft.com/en-us/library/windows/desktop/aa386526%28v=vs.85%29.aspx" rel="nofollow noreferrer">Search function</a> but I can't find a criteria to do that.</p>