Hi,
Since Android 4.4, Google has limited the data one can move into an SD card -unless you root your phone. Only apps and Android itself can move files, but Solid Explorer or other file browsers can't ("this is caused by new external storage policy introduced by Google in Android 4.4").
I would suggest or request changes to GoldenDict for Android -at least for the paid version, which I paid for- so the app itself can move the dictionaries into the SD card. The option of "extra folder" or "additional folder" is not useful anymore -unless one wants two different folders in the memory of the device, I guess some people might need that.
Thank you very much!