I always pass exams but how can I convince employers in an interview? ماذا أفعل لأقنع صاحب العمل بنفسي في المقابلة الشخصية؟

It is simple all u have to be is confident about yourself .It might be lack in presentation skill creates the problem.
If you feel that you lack in language go for some training.If not practice by yourself try to work in such a way that when you go for the interview you will feel confident in presenting yourself.