Maybe it's because I signed up for Google+ out of professional curiosity and have not returned to it after the first couple of weeks I signed up and made a few G+ friends and circles, but I have found little to no use for Google's new Search plus Your World feature. It delivers personal search results from the friends you follow on Google+ and Picasa. Thankfully, it's easy to remove these results for a particular search or disable the feature for all searches.
At the top of some search results pages, Search plus Your World adds a link for a number of "personal results." To the right, you'll see two buttons to show or hide personal results. Click on the button with the globe icon to hide results.
To disable the Search plus Your World feature altogether, click on the gear-icon button in the upper-right corner of a search results page and choose Search settings. On the next page, scroll down to the Personal results header and click the dot for "Do not use personal results." Then scroll down to the bottom of the page and hit the blue Save button.