1. A method for providing an electronic book, comprising: receiving a query; performing a search according to the query; and generating the electronic book according to a search result responsive to the search; and displaying the electronic book as the search result, or sending the electronic book to a pre-specified client, a pre-specified network disk or a pre-specified mobile terminal; and further comprising: obtaining a piece of first copyright information of the plurality of search results and a piece of permission information of a user; and generating a piece of second copyright information of the electronic book according to the piece of first copyright information and managing an operation permission of the user for the electronic book according to the piece of permission information of the user, wherein managing the operation permission of the user for the electronic book according to the piece of permission information of the user comprises: storing the electronic book in a cloud server as a mother book; and generating a child book corresponding to the mother book according to the mother book and the type of the client and sending the child book to the client, wherein the child book comprises a child information file and the child information file records a position of a page of a content in the child book in the mother book, wherein the method further comprises: receiving by the client an operation instruction; and obtaining by the client a position of a content corresponding to the operation instruction in the mother book according to the child information file and obtaining by the client the content corresponding to the operation instruction from the cloud server according to the position.