<http://schema.org/thumbnailUrl>
<http://cdn1.tnwcdn.com/wp-content/blogs.dir/1/files/2012/06/4308934521_18ac6406ed_z-520x245.jpg>
<http://thenextweb.com/lifehacks/2012/06/22/nifty-google-search-lets-you-filter-out-search-results-youve-already-visited/>