We've recently extended the custom search capabilities of the Webvanta system to handle nearly any need. You can build custom search forms that allow a user to choose from a variety of taxonomies and other fields, and specify search criteria that is a combination of AND and OR functions. You can pass the parameters to the search results page in a variety of ways, and find either database items or uploaded files using the criteria.
There's a lot of complexity here, given the flexibility of the system and the range of things you might want to do. We don't yet have user documentation that explains it all. So if you're looking to build something that requires elaborate criteria for what items are displayed, contact us and we'll help you set it up.