Many apps do not allow for moving to an SD card. If that is the case with any you are trying to move, they won't give you the option to do it. There really is no way to make them move. In the case of downloading directly from google play store to the sd card. This feature is available only on Android Version Marshmallow. In any other lower Android, you can only download apps and then move them (if they allow moving).
You could, however, move any pictures, sounds and videos over to your SD card. That would give you a lot of space. Just be sure to make backups of all before moving them, to say a computer, could, etc.