Graph with combination of 2 Legends

Hi

I want to show graph where 2 data series will have different legends. If i just add 2 data series Legend is one & i can assign value or it will take automatically. But in my case 2 data series should have different legends for better visibility.

Example - I want to combine graph of sales quantity & Sales Value. Value will be in millions always & quantity will be in hundreds. & I need to show this in one chart.

Regards

Deepdas