I have a list of header_list as header1,header2,header3.

I need to display header1 & header2 in Form design of Reports in OpenERP 7 in one case and then

I need to display header1 & header3 in 2nd report of the same object/table.

For example:

If in sales order, the order_line containing the attributes of product is provided.  In my case, I have to show fields respective to the product chosen and values to be entered.

How can I obtain my report without any whitespaces in places where the field value is NULL