1. A computer-implemented method, comprising: at a computer having memory, a display, and a processor, identifying multiple resource identifiers in accordance with a first set of predefined criteria for selecting a respective document that satisfies user-specified search keywords from a user, each resource identifier corresponding to a document at a respective data source; and for at least one of the resource identifiers, retrieving the corresponding document from the respective document source; identifying within the retrieved document a chunk by applying a second set of predefined criteria to the retrieved document; and providing the identified chunk and a link to the identified chunk within the document for display to the user, wherein the first set of predefined criteria requires that at least a first subset of the search keywords be found within an identified respective document, and the second set of predefined criteria requires that at least a second subset of the search keywords be found within an identified chunk.