Internal site search is a core component of most e-commerce sites, but it's rarely optimised to its full extent.
Tools such as Fredhopper, Endeca and Adobe Omniture Merchandising can help enormously in this matter but there are certain generic tasks that anyone can perform to help optimise their internal search, no matter what tools you're using.
1. Make sure your search delivers relevant results for product name searches, including any SKU numbers or product reference numbers that you use.
This can be achieved by applying the right attributes to your catalogue and ensuring that these are surfaced through the search journey at the right time.
Use your analytics to identify your 100 most-searched keywords, then test each one in your search box. Are relevant results shown first in the product listings (and preferably above the fold)? If not, ensure the search keywords appear in your catalogue data within the relevant products, preferably within the product's title.
Depending on your catalogue size, your top 100 search terms will normally cover the majority of internal searches on your site. If you're a new site with no history of internal site searches, try optimising for your SEM keywords instead.
2. Eliminate as many zero search result situations as possible
Use your analytics to identify what your visitors were searching for when they exited your site. Massage your catalogue data to ensure relevant products appear for these search terms.
If you can't find appropriate products to show for a particular keyword, at least try to offer some alternative products in order to keep the customer journey flowing. You could try showing your three most-searched-for products here, or three top sellers.
3. Beware 'long descriptions'
These can often be the source of irrelevant search results. If you're using a search management tool, you should be able to deprecate the importance of long descriptions to search, versus short descriptions, SKUs and products keywords.
4. Try to redirect non-product searches to relevant pages on your site
Visitors type all kinds of things into the search box, particularly when they're lost. What happens on your site when you search for the following terms: help, delivery, returns, guarantee, customer service, store finder, stores.
If you're not redirecting these terms, you're missing a trick.
5. Treat optimising your internal search as a regular weekly or bi-weekly task
Most e-commerce catalogues change at least seasonally, and your top search terms will change accordingly. A small amount of time spent on the above tasks should pay back many times over. Monitor your analytics closely and keep testing and improving your search over time.
Also monitor suitable KPIs for search, for example percentage of visitors using the search box versus navigation on your site.