Hi Ram Bilas yadav
Don't think you need to use groups. Try the following.
-Click on the repetitive area. If 2004 make sure you click right on the edge of repetitive area and like a border is around it.
- Then right click or use the PrintLayout designer menu at the top. If right clicked you'll see there is a sort. Go into it. If you wnet via the menu at top, go to repetitive area->sort.
-Once you are here you can say how you want to sort, summarize it and even say a new page for each like summarize.
Hope this helps
You have a good help file about document editing here:
Under CustomizingDocument Editing Layout designer in release 2004 A
Have a look at the subsort and subtotal part.