Root [Sprint] Can the S4 READ a USB drive?? HELP!

Hi all,

I know this is a totally noob question but im trying to figure out if I can read/write to an external USB drive plugged directly into my phone?? (Sprint Samsung Galaxy S4 SPH-L720, rooted and flashed with ForceRom)

I've used file explorer to try to locate the USB after plugging it into the phone, but I can't seem to find it or any of its contents....could I just be over looking them, or would they not be displayed?

When I search for "How to Guides" all I can find are instructions for enabling Mass storage, which allows for direct file transfer between your desktop and the S4s' external SD card, and unfortunately that's completely unrelated to what I'm trying to do.

Any help would be appreciated, thanks in advance!!