Smart Search component have built since Joomla! 2.5. It's still improving for next releases. In order use this component, you must enable all plugin related to this component. Go to Plugin manager > enter keyword "smart search" and enable these plugins.

joomla ajax search module



Next, in Smart search component, click Index button to recrawl data. Processing times depend on your website data. Because all data of Smart search is static, so you should recrawl data several times/week.

joomla ajax search module



Finally, create a Ajax Search module. Go to Module manager > New > Smart Search module.

joomla ajax search module



Then set all necessary parametes and save it.

joomla ajax search module



The result as bellow:

joomla ajax search module