MENLO PARK, Calif. — Facebook CEO Mark Zuckerberg unveiled a new search feature that’s designed to entice people to spend more time on its website and will put the social networking company more squarely in competition with Google and other rivals such as Yelp and LinkedIn.

Called “graph search,” the new service unveiled Tuesday lets users quickly sift through their social connections for information about people, interests, photos and places. It’ll help users who, for instance, want to scroll through all the photos their friends have taken in Paris or search for the favorite TV shows of all their friends who happen to be doctors.

Although Zuckerberg stressed that “graph search” is different from an all-purpose search engine, the expanded feature escalates an already fierce duel between Google and Facebook as they grapple for the attention of Web surfers and revenue from online advertisers.

“This could be another reason not to use Google and another reason to stay on Facebook for longer periods,” said Gartner analyst Brian Blau. “I don’t think Google is going to lose its search business, but it could have an impact on Google by changing the nature of search in the future.”

Facebook’s foray into search marks one of its boldest steps since its initial public offering of stock flopped eight months ago amid concerns about the company’s ability to produce the same kind of robust earnings growth that Google delivered after it went public in 2004.

Although Facebook’s stock has rallied in recent weeks, the shares remain below their IPO price of $38. Investors seemed let down by Tuesday’s news, causing Facebook’s stock to slip 85 cents, or 2.7 percent, to close at $30.10.