Select 'Demat Holding' icon from 'Menu' option to view all the Holdings available for Sale.
You could also view your holding in SBI Trading Account at:
Visit www.sbismart.com
Click on Login -> Trading Account
Go to 'Portfolio Screen' under 'Menu'
Portfolio screen consists of 3 Tabs (Current Holding, Zero Holding and Negative Holding). Current Holding indicates the holding available with you for selling.