Microsoft has unveiled major changes to its Live Search service intended to give it a better foothold in its ongoing battle with Google.

The Redmond giant has concentrated its improvements on the nuts and bolts of the search engine, enhancing its core search technology and strengthening the vertical search areas of entertainment, shopping, local and health.

"With this update, our engineering focus is on the areas that matter most to the 185 million consumers who use our service every month," said Satya Nadella, corporate vice president of Microsoft's Search and Advertising Platform Group.

"We know what kinds of things consumers are searching for, and we have invested in those key high-interest verticals, including entertainment, shopping, health and local search.

"With the core platform in place we intend to win customers and earn their loyalty one query at a time."

Up to 40 per cent of searches fall into the categories of entertainment, shopping, health and local search, and the enhanced Live Search is geared towards delivering relevant content in a compelling way across these key vertical search areas.

A new video search feature offers smart motion previews, facts and news on celebrities and a new xRank celebrity ranking tool.

The shopping and health searches have also been refreshed to derive the most relevant content from trusted sources, allowing consumers to refine searches faster and with more accuracy.

Microsoft has increased its index size more than fourfold as almost 20 per cent of customer challenges came from the 'long tail' of the web, indicating a need for broader coverage.

Live Search now claims to do a much better job in predicting the intention of the query to return the best results possible, despite common problems such as spelling errors, stop words, punctuation and synonyms.

The search engine is even capable of making proactive changes to the query in cases where the engine is confident of the customer's intention.

Additional improvements include a cleaner user interface that makes the results pages easier to read and use, and a more robust Answers platform that provides instant access to information from trusted sources while increasing relevancy.