Grouping grand total

Dear SAP Experts,

I kind of got a case with bex query.

Because of join table, I have query data in bex like this :

Sales order# Material# Billing# Bill Amount COGS Net SO Amount

S1 M1 B1 1000 2000 6000

S1 M1 B2 500 2000 6000

S1 M2 B3 800 3000 6000

S1 M2 B4 400 3000 6000

Grand Total 2700 5000 6000

I want to have total for bill amount column = 2700 ,

For COGS total = 5000 (group by Sales order# and Material#),

For Net SO amount total = 6000 ( net so amount group by sales order#).

Could help me give some way to achieve the results?

Kindly help and may thanks

Regards