title: select from list not containing particular item in linq
body: <p>I have two class.</p>
  
  <pre><code>public class Category
  {
     public int Id {get;set;}
     public string Name{get;set;}
  }
  public class Product
  {
     public int ProductId{get;set;}
     public string Name{get;set;}
     public List&lt;Category&gt; ProductCategory {get;set;}
  }
  </code></pre>
  
  <p>Now i have Category list based on that i need to get product  </p>
  
  <pre><code>List&lt;string&gt; filtercategory ={"HomeMade","Uncooked"}.
  </code></pre>
  
  <p>I need to all Products which doesn't belong to 'HomeMade' and 'Uncooked'.</p>
  
  <p>What should be linq query logic on this?</p>
  
  <p>thanks.</p>