According to reports online, Google will be implementing “semantic search” to analyze the meaning of words and phrases typed into the search query box to return answers instead of just a list of ranked search results.
For example, you may want to find someone knowledgeable about real estate in a specific neighborhood to ask for buying advice. But the right person may not list that as an “interest,” so you may not be able to easily find them in your expanded network (which includes friends of friends). A semantic network would find the right person to talk to by analyzing which people in your network post content having to do with the specific topic, and how much time others spend reading it.
By retrieving based not on one query but on several semantically related queries, the search becomes more topic oriented rather than matching only on a few words in the original query.