The Segmentation feature in Angelfish allow you drill down into details for each Dimension row.
To access these details, click the magnifying glass icon to the left of the row number in any report. The available segment options will appear.
Click the option you'd like to segment the dimension with, and the data will appear underneath the dimension row. You can open multiple segments underneath each dimension row - they will stack vertically.
To close the segment, simply click the X in the upper left corner of the segment.