Pivot tables have the flexibility to include intended measures (Total $, untaxed $, Qty ordered, Qty delivered, Qty invoiced.. et al) and rows and columns can be expanded to include products & customer etc.

The tutorial below illustrates the usage, (1.35 mins). Though the reporting example in the tutorial is from projects app, it is consistent across all apps

https://www.odoo.com/slides/slide/reporting-1615?fullscreen=1

Thanks this is the first step. But if it wasn't clear, I want Turnover and quantity of products sold per customer.