You can drill down on dashboards in 3 ways;
By clicking on the 'View raw data' option in the menu which appears on the the top right corner when you hover over dashboard gadgets. This will always provide a tabular view of the underlying data.
If a drill down view has been configured for a given gadget, a 'Drill Down' option will be displayed on the gadget. Clicking this will drill down to a relevant report and apply any filters that were set at the dashboard level such as date or selected drivers.
Drill down on filtered raw data by clicking on chart segments
