Facebook just upgraded its search engine feature. By this week, the new tool lets users search for real-time news, including all public posts.

As mentioned on Facebook's newsroom, the site's search engine now offers timely, personalized search suggestions. Like on Google or Yahoo, Facebook search highlights things that are happening so the user can follow popular stories.

The upgraded search engine also shows the most recent, relevant public posts from user's friends. The user is also able to see the latest public post by doing pull-to-refresh.

The search result on Facebook is now able to find public posts about a link, the user can see popular quotes and phrases mentioned in the posts, and check out an aggregate overview of sentiment.

For the users who don't want their posts to be public consume and searchable globally, make sure to remove all posts from public view with a few clicks on Settings option, including the old posts.

If you want your posts to be included on Facebook Search, choose Public on Settings. If not, go with Friends. And if you want to keep it private, click on More Options and select Only Me.

But if you don't want to change the settings on every single post, it is advisable to do search test: search some topics you often post about with Facebook's new tool. You can delete any problematic status updates, photos, or any of your posts on the search result that you wouldn't want other users to see.

The Facebook's universal search tool could compete with other social media platforms like Twitter. The public is now able to instantly see what everyone is saying about a topic on Facebook's search, as they do on Twitter.

As mentioned on The Verge, the tool asks users not to head on to Twitter to find out what's happening at the moment, but to stay on Facebook and search for it.

The upgrade also competes with Google search. Years ago Google had anticipated Facebook by launching Google +.

But as reported on Huffington Post, Zuckerberg already had told investors last year that Facebook was going to compete Google on search directly. The Facebook's new search tool is his actual move.

The universal search tool also opens the possibility that Facebook would advertise in the future by targetting users not only based on the webpage that a user visits, but also based on anything that user post about on their Facebook account. However, Facebook hasn't confirmed this new possibility on its ad service.