Add the same coding to the top of 'search_result.tpl' and you will get the same effect on your search results.
i.e. if there is only one search result, it will show full details.
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and use the following mod as well:
Search by SKU/Product code in quick search - 4.1.1
http://forum.x-cart.com/viewtopic.php?t=29877
and you can have it so when someone puts in a SKU in the search box, the full details appear instantly.