Yes, you can apply for more than one course. Please be aware that if you are already registered for another course, you will have to finish that registration and application first. Otherwise you cannot apply for another course.
After you have finished your registration/application, please go to the home page of the online application system. You can click on the ‘Apply to another programme’-button to apply for another course.
When you apply for another course, you will have to send a new motivation letter for that specific course. It is not necessary to upload the other requested documents again (e.g. your cv, diploma, etc.), they are already in your application file.