If you want to narrow the expanded list of items in the Outline view, you can use the Collapse All Trees toolbar icon on the Outline view.
To quickly collapse the tree to the left of a selected node under a program, right-click that node and select Collapse Trees.
The Outline view collapses the selected node hiding the fields within the program.
Note: Alternatively, you can click the View toolbar icon
on the Outline toolbar and select Collapse Trees from the drop-down menu to collapse the selected node. To collapse all expanded nodes, click the Collapse All Trees toolbar icon
on the Outline view.