There are a number of controls and breadcrumbs that determine the display of the Resources tool, making it easier to maneuver about within the tool.
Selecting the name of any subfolder will isolate the display to just the contents of that subfolder.
Subfolders containing content will display as a closed folder icon with a white plus sign. Selecting a closed subfolder will open it.
Selecting Expand All will open up and display the contents of all folders and subfolders. Selecting Collapse All will close all folders and subfolders.
Expand All/Collapse All is a toggle button. Selecting it once will expand the display; selecting it again will collapse the display.