content drilldown reports in google analytics shows your website pages and subpages. When viewing in google analytics home page will be displayed as ‘/’.
Why google analytics does not show subpages/content drilldown?
If your site is not structured well and is not categorized into folders and subfolders you might not be able to see content drilldown reports. If you have installed cross domain tracking you might not see the content drilldown reports.
How to view content drilldown reports for cross domain tracking?
In order to view content drill down reports you would have to add a filter. Below is a screenshot for your ease.