1. A method performed by a mobile device, the method comprising: receiving an image optically captured from a textual portion of a rendered document; determining multiple text strings from the image; generating multiple search queries, each search query comprising a respective one of the multiple text strings; sending the multiple search queries to an Internet search engine at a location remote from the mobile device; receiving, at the mobile device and from the Internet search engine, multiple respective sets of search results determined by the search engine in response to the respective search queries; determining from the multiple respective sets of search results a first search result that most likely identifies an electronic content counterpart of the rendered document; and providing, for output, the first search result.