Click on library, Public Shared, then documents .... select first file & whilst holding down shift key scroll down to last & select it, then right-click & choose Remove from Library.

Another similar way to do it is click on Public Shared -> All, then right-click heading bar & choose show Type. Then click that heading so it arranges files in order of kind of file. Scroll down to Documents, select the first one, then scroll down to the last Image type whilst holding SHIFT key & select it & then right-click it & choose Remove from Library. That will remove all documents & images from sharing in a single action.