title: Using NSPredicate to filter array of arrays
body: <p>I have the following situation:</p>
  
  <pre><code>NSArray(
      NSArray(
          string1,
          string2,
          string3,
          string4,
          string5,
      )
      ,
      NSArray(
          string6,
          string7,
          string8,
          string9,
          string10,
     )
  )
  </code></pre>
  
  <p>Now I need a predicate that returns the array that contains a specific string.
  e.g. Filter Array that contains string9 -> I should get back the entire second array because I need to process the other strings inside that array. Any ideas?</p>