The default Search function in Magento is not offering your customers much comfort, or you as Magento shop owner much sales…
This article describes how to use the open source Search Engine Sphinx within Magento. The added benefit is that it offloads the search work from your server processor to the Sphinx engine.
Method 1: manual labor:
If you feel comfortable doing the work yourself, here are two links that will teach you how. The first link is a more step by step approach, and seems more up to date. The second is for reference, and is more focussed on older Magento versions, which may come in handy for some.
Link 1: http://www.mediawiki.org/wiki/Extension:SphinxSearch
Link 2: http://tonyhb.co.uk/2012/05/using-sphinx-within-magento-plus-optimising-search-result-rankings-weights-and-relevancy
Method 2: Install an extension:
There are several extensions which do the hard work for you. I name a few, if you know more extensions that do the trick, let me know.
Method 3: Other search tools for Magento:
Obviously, Sphinx isn’t the only way to go. Here is an article on some alternative extensions that will improve Magento search: