Required to build a custom search module for zencart, where it checks for words in the product title and description and adds the possibility to add search keywords to the products has an aditional product creation field. The idea is to provide search results based in relevance, for istance, keyword found in Title/Manufacturer -> Product Keywords/Tags -> Short Description -> Product Description.
It is also very important to add a mispell engine capability, for instance, something based on previous serach, like if you are search for "green apple" and mispell green or apple, it still delivers the most apropriated algoritmic results or at least provids a search correction like Google, example "Where you searching for green apple".
A Jquery autocomplete search capta would be cool to add also.
Trackig is a major, in according to the already search tracking free modules it is important to track the latest searches accordingly by date/time and to provide a summary of the most searched keywords by date range.