GCMS notes received. Only same lines written as in rejection letter.
Hey,
So, first of all - you have to fix all the concerns of the VO that are given to you in all your applications, mostly being your ties to your home country, your job stability, perhaps your travel history, and your ties in Canada. All of that may require you to wait a year or so before reapplying, maybe apply to the US for a vacation and actually visit (like others have suggested). You would also build your ties with Pakistan with time. Once all of that is done, write a detailed explanation letter (you are a professional you should now how to write a nice letter) with you next application as to why you think you quality for the visa and how you have taken measures to address the concerns listed in your previous applications. I always say that and I can't emphasize it enough, always use the optional explanation letter to build that personal rapport with the VO. Since there is no interview (in most cases) for Canadian visa as opposed to a mandatory interview for the U.S. visa, it is important that you take advantage of the explanation letter. Make sure you back up every statement with an evidence/official document etc.
If you think you have the answers to all the visa refusal concerns already and you are keen to reapply for the fifth time, you sure can. But again, provide detailed explanation and defend your case properly. Always remember, it is the applicant's responsibility to convince the VO that he/she, if granted a visa, will obey the regulations of the visa, one of which is returning back in a timely manner after your visit.
Good luck!