Google has probated its latest technology about the number of images embedded in a web page and list of thumbnails above the snippet. It all done after extracting a lot of interesting information from web pages like dates, locations and author names.
However, unfortunately this feature is not available for everyone. If it will be launched the result will show the enhanced snippets for pages that embed many images.

Click to filter file types in Google search results

The similar option about the snippet is, if you will click on “Search options” and select “Images from the Page” as shown in the picture. If you look at the result, you can see two thumbnails next to each search result.

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