My cousin and I have tried this many times i just do not find any problem, we are both beginners so I would not be surprised if there was a stupid mistake in this. I keep receiving an error message; Oops, try again. Add a < div class="thumbnail">..</ div>.
You opened two div's above your code and you've not closed them.
Your first two div's needs to be closed.
The error messages are very limited.
Where is the
</div> that closes your first col-md-4?