2. The method according to claim 1 , further comprising the step, to be performed by the computer, of, outputting a display screen including the extracted elements.
2. The method according to claim 1 , further comprising the step, to be performed by the computer, of, outputting a display screen including the extracted elements. 3. The method according to claim 2 , further comprising the step, to be performed by the computer, of, if information instructing a creation of the index is obtained, creating a path of the extracted elements in the logical structure index as the index, after the step of outputting the display screen.