vb.net remove from 2d list based on 3 subitems

[t2nator]

I have two list of list of object's, based on three subitems of list1 if those subitems exists on an item of list2 then remove that from list2. I keep finding rows from list2 that exist in list1 and i am out of ideas.

Dim list1 As New List(Of List(Of Object))
Dim list2 As New List(Of List(Of Object))
Dim it As Integer = Nothing : Dim it2 As Integer = Nothing
While it < List1.count
    While it2 < list2.Count
        If list1(it).Item(0).ToString = list2(it2).Item(0).ToString And list1(it).Item(3).ToString = list2(it2).Item(3).ToString And list1(it).Item(6).ToString = list2(it2).Item(6).ToString Then
            list2.RemoveAt(it2)
        End If
        it2 += 1
    End While
    it += 1 : it2 = 0
End While