Guys Please don't give any "advice" if weren't sure of what you were talking about.
There are many people (including me) who got visa from a diplomatic post outside their home country.
It differs from person to person and it isn't one cure for all.
If you think that you can show that your primary intention is only to study ie., showing that what ever you are going to study is to enhance your career but not a bait to get your PR. Also you have to show a steady income, good academic background and most importantly you should be able to convince VO that you can survive outside Canada even if you fail to secure a PR after your proposed studies.