Are you advertising your courses on your site? Are you searchable? Are you advertising your site?Who are your potential students? Where are they? Are you letting them know where you are? And do you have something of interest for them? Where is your site? If nobody knows, nobody will go to look or consider your courses.
You said your students. If you already have students in a face to face classroom for example like I have, then what you do is list your users as administrator, with their email addresses, and invite them to join your moodle courses. If you want to expand the number of students you have, then try for example putting up some flyers with your website address, in locations where your potential students might find them.