The Supporting Documents module is made up of two main 'panes' - the checklist and the documents bucket:
You might find it useful to expand (or collapse) panes to be able to have better visibility of particular items.
To expand a particular pane so that you are only looking at that particular pane, you can click this icon in the top right of the pane:
Here I have clicked to expand the Documents Bucket:
And then I have clicked "Large Icons" to get a better look at my documents:
If I then want to go back to the original view, I can then click on either the same icon in the corner, or click on "Default View":
L-M-R
You will note another set of controls that are L-M-R.
These allow you to open/close each of the 3 panes in Supporting Documents as you wish:
You can play with these controls to manage the visibility of your panes as you wish.