Use title in URL

Hi
In my shop project,i need show product title in url
Example:
example.com/product/laptop sony/vio
laptop sony/vio is product tite

How do some sites show title in url and encode and decode it and search product?

In codeignter we can use below code
$title = "Agile Digital Project Manager/£475 - 525 pd/6 months/London";
$url_title = url_title($title, 'underscore');

But how do decode it?