Google Search options are a set of filters for refining the search, Google added them few months back to web search and for image search. Today Google added some more filters to the web search for better search experience.
There are a total of nine search options enabled today. These include past hour, specific date range, more shopping sites, fewer shopping sites, visited pages, not yet visited, books, blogs and news. You can open the search options panel by clicking on the search options line above the search results.
Google search options earlier included filter for restricting search results to past 24 hours, past week, past year etc, today they enabled Past Hour and specific date range filters. Past hour is good for the folks who are into real-time search.
More shopping sites and fewer shopping sites option allows you filter product search results from shopping sites. If you are not sure where you want to buy a product you can use more shopping sites, and if you are almost decided you can exclude many shopping sites by using fewer shopping sites option.
Books, Blogs and News options will allow you to narrow down your search to only these categories.
The other interesting feature that is added today is Visited pages, this allows you to search only sites that you already visited. For this feature to work you are logged in to your Google account and enabled the web history.