Hi, Kusnardi...
If you place the mouse in the group definition area (on the left-hand side of the screen), right-click, and select "Section Expert", you'll see check-box options for "New Page Before", "New Page after", etc.
Sometimes I'll check "New page after" in the group footer, and include a formula using the "NextIsNull" function on the group definition, to determine whether the action should be done or not.
Hope that helps...
Kevin