Let them Search Or They Will Leave
Site Search is the Holy Grail for Ecommerce websites. You could have great products, great pricing, but if your customers can't find what they are looking for, then it's like having a website that no one visits.
If you are using a site search that doesn't allow for fuzzy words or mispellings, then you need consider upgrading. Another wonderful feature is some of the more popular site search engines is "related words". If someone types in a word, you can redirect that word to another more relevant word. Example; the correct word is a "fishing rod" NOT "fishing pole" No products are labeled "pole" so if someone searches for "fishing pole" you can re-direct that search to "fishing rod". This is very powerful and very useful. This allows your customers to search on what THEY know and not what YOU know, making the whole shopping process smoother.
Not really a site search feature, but a tip. Consider logging all the terms used in your site search. Then take a look at your top searches and utilize this information to promote those products, make sure your search engine is outputting what these people are looking for, find related words (ie pole vs rod). There are all kinds of marketing ideas that can come from looking at what your customers are looking for on your website.
Again if customers can't find products either by navigating or by searching your site, you will lose out on many sales.
If you haven't already consider evaluating your site's search features and adjust accordingly.
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Thoughts?
Another related thought by logging the search terms, it may help merchandisers procure additional products or new products. If you site is attracting a customer looking for product X, then you should have product X or at least product Z which is just like product X available to the customer.
Yet another side note, if you output your popular search terms for your customers to see. This will 1) allow customers to see what you have and suggest items they didn't realize you had 2) easily find items that they are most likely interested in and 3) add keywords/content to your site for search indexing.
As you can see, Searching on your site has alot of good results and power.. booooost it up!