Answer:
Please use the following steps to add Voucher type name in tax register.
- Go to Main Menu > Financial Management > Reports > Tax Register(F> R> A)
- Press F2 and enter date range
- Alt + S (or use “– S sale Inv” button)
- Ctrl + R (or use “^ R Columnar” button)
- Right click on Report Header
- Click on “Show field List”, it will open a list of variables.
- Drag “Voucher Name” from the list and drop it on the report header
- Press F10 from keyboard
- Enter a meaningful name and save the layout for future use.

For more detail please visit: http://www.rancelab.com/help/fr6_tax_ragister.htm