Hmm... That's not an easy job...because I imagine that in some situations, you would want your search engine to find synonyms. For example, let's say I am searching for a "4TB hdd." It should understand the word "hdd" and automatically look for the words "hard drive" and "hard disk" and "ssd" as well. BUT if I were to search for the words "2007 Dodge Caravan rear brake pads" then it would be really annoying if it also showed me Ford brake pads just because they are both cars.

One time I wrote a stock search engine in JavaScript. But it's very-very simple. It wants you to type in a name or part of the name of a company. Then it lists all the companies that have that word in their name. So, for example, you enter the word "nano" and it will display every company whose name contains the word "nano." It loads all the company names into memory first, which takes a few seconds. But once the page loads, then the search results appear at lightning speed. http://wzsn.net/stocksearch.html