You can use different techniques to see different parts of the object tree.
To move vertically through the current display, use the scroll bar on the left or right pane.
Click the plus or minus buttons. A plus button next to an icon indicates that the list of objects for that icon can be expanded. A minus button indicates that the list of objects for the icon is fully expanded.
Double-click a folder icon, which expands the list in the right pane and changes the view to a list of objects in the folder. For most objects, double-clicking an object icon in the right pane opens a property sheet that displays information.