ImportXML query giving internal error

I have just wrote my first ImportXML function to fetch the products like this. I want to fetch all h3 elements. But its showing import internal error.

=ImportXML("http://ift.tt/1y9Bah1","//h3")

I tried this query also to give all the h3 elements with class r, but its still showing the same error?

=ImportXML("http://ift.tt/1y9Bah1",
                "//h3[@clsass='r')")