Today Google added two new features to Google Search. First feature offers an expanded list of useful related searches and second one is longer search results description. Google employed a new technology that can better understand associations and concepts related to your Google searches and one of the first applications offered by Google is useful related searches.
For example, if you search for [principles of physics], our algorithms understand that "angular momentum," "special relativity," "big bang" and "quantum mechanic" are related terms that could help you find what you need. Here’s an example (click on the images in the post to view them larger):

With this new technology Google will be able to target more queries, more languages and Google suggestions more useful for users. Google search is also offering refinements for longer queries . User will be able to see Google’s new related searches starting today in 37 languages all around the world.
Google increased the number of lines in snippet to provide more information and show more of the words to users typed in the context of the page. Couple of examples that are mentioned in Google blog are
Suppose you were looking for information about Earth’s rotation around the sun, and specifically wanted to know about its tilt and distance from the sun. So you type all of that into Google: [earth's rotation axis tilt and distance from sun]. A normal-length snippet wouldn’t be able to show you the context for all of those words, but with longer snippets you can be sure that the first result covers all those topics. In addition, the extra line of snippets for the third result shows the word "sun" in context, suggesting that the page doesn’t talk about Earth’s distance from the sun:
Source : Two new improvements to Google results pages