MStardict or any other dictionary app is like a shell or a house, there is no content in it yet.

You may find many dictionaries on internet for download and they are all zip files. You download those zip files into your computer and then unzip them. Connect your phone to the computer and select "Mass Storage Mode" on your phone. You should find a MStardict folder in the phone memory. Copy the unzipped dictionary folder and paste it in the MStardict folder. After that, open the MStardict app., go to setting and check the dictionary.

TC