When I search for a configurable product (by name, name fragment or SKU) the search does not return any configurable products. I can search for simple products.
The configurable products;
This is a multi-store setup and this issue only affects one store, so I'm assuming it's a configuration issue, but I can't find any setting that might stop configurable products being returned in a search.
I'm open to suggestions on this one, I'm pretty sure I've overlooked something silly - I just can't work out what!
I tracked the issue down to a third-party search module. If you're having the same issue, disable any third-party modules that replace the standard Magento search function. If the problem still exists, see the other answers here for some good advice. If the issue resolves, you may need to contact the module publisher.