1. From the home screen, select the Google Folder > swipe left > select the
Files app.
2. Select the
Menu icon, then select the device.
Note: If you are prompted with a permissions notification, select ALLOW. 
3. Navigate to and select and hold the desired file(s), then select the
Menu icon. Select Copy to.... 
4. Select the
Menu icon, then select SD card. Navigate to the desired folder, then select COPY. 