31. A computer-implemented system comprising: one or more devices to: identify a document that is relevant to a search term, the document comprising structural elements; identify occurrences of the search term in the document; group the occurrences of the search term into clusters based on a threshold that specifies how close in physical proximity two occurrences of the search term have to be to be clustered, the threshold being proportional to a number of pages in the document; determine a structural element, of the structural elements, encompassing each of the clusters; and provide, for presentation, information related to the structural element.
32. The computer-implemented system of claim 31 , where the document is a book, and the structural elements include the book, a set of chapters of the book, and a set of pages of the book.