How to show more lines in a subpage of a worksheet

Hello,
We build a worksheet with a subpage to enter the ordered Qty in a temp field from the 'offer-lines', to copy them to the sales lines. The sales Lines are shown in the subpage of the worksheet. How can change the size of this subpage? I want to show more lines. De "double lines" do not show up moving the mouse.



Any suggestions?
Carolien