After you select an area on the map, you can select all admin boundaries that intersect your selection by using the Intersect Area with Admin Boundaries tool.

To select this tool, click the arrow next to Modify Selection in the map tool bar.

Click Admin Boundaries under Intersect Area with Grid.

Then click the selection you want to intersect. Your selection will be intersected with the grid.

Note: This tool is not available for pre-cut tiles products.