Google has unveiled four new products in an effort to improve the accuracy of online searches. 

The search firm has been concentrating on non-search products of late, such as Gmail, Google Talk and Google SketchUp.

But the company emphasised during a media and analyst event at its corporate headquarters yesterday that search is, and will remain, at the core of its business. It added that search attracts about 70 per cent of its resources.

"All these [new] products are centred around search," said Marissa Mayer, Google's vice president for search products and user experience. "Our core, and where we innovate most, is inside search."

The new Google Trends lets users search information about people's interests based on queries that have been submitted to the service in the past. 

It promises to display which queries were popular on a particular date and which geographies are interested in particular subjects.

The company currently offers the Zeitgeist service, publishing information about popular searches in a particular month.

"We're giving you the keys to the Zeitgeist kingdom," said Jonathan Rosenberg, Google's senior vice president of product management.

He added that the service could be useful to marketers as they research consumer interest in their products or particular trends in certain geographies.

Google Co-op includes search results from a list of selected specialist partners that list information about specific sectors. Users have to opt in to have results from these sites included. 

The search firm partners with sites including Open Table, Digg, People magazine, Wine Spectator, Gap Minder and Fandango. Partners are included free of charge. 

Listing search results provided by qualifying partners will make for more accurate search, Mayer claimed.