umbraco ver is 7.0.2, umbraco.config data like this:

<division>
    <newsCenter>   
      <news>
      </news>
    </newsCenter>    
    <newsCenter>
      <news>
      </news>
      <posting>
      </posting>
    </newsCenter>
</division>

here is my code:

foreach(var item in division.Descendants().Where("NodeTypeAlias == @0 || NodeTypeAlias == @1","news","posting")
{
    <li>@item.Name</li>
}

i want get all news and posting ,but result only has news without posting, very strange, Could anyone point me in the right code,many thanks