As far as, i know about this refusal that "I'm not satisfied that you'll leave Canada" or "you don't seem to be a bonafide student", i believe that it has nothing to do with your IELTS score or industrial experience or other formalities. Its all about your SOP. Visa officer wants to know why you applied for this particular course? Whether it is relevant to your prior education. In some scenarios, it might be possible that your course selection makes sense for you and for your future prospects. In that case, your SOP helps the VO to believe that your intention for coming to Canada is absolutely fine.
I read an experience of a user who shared his timeline here at canadavisa forum. He has done his bachelor in civil and wants to do management regarding course from canada. His application got refused and the reason was same. "I'm not satisfied that you're a bonafide student". The applicant was sure about his course selection as he was sure that management knowledge will help him in carrier prospects.