score:1
Your passport doesn't get you a visa waiver, but your Canadian visa does, if you are flying from or to Canada, which seems to be your case.
https://en.wikipedia.org/wiki/Visa_policy_of_South_Korea#30-day_visa_exemption
Upvote:1
Per Timatic, the database used by airlines:
Visa required, except for Nationals of Viet Nam with a visa issued by Australia, Austria, Belgium, Canada, Cyprus, Czech Rep., Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland (Rep.), Italy, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Netherlands, New Zealand, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, USA or United Kingdom if in transit through Korea (Rep.) must
-hold confirmed onward tickets on flights departing within 30 days when arriving from the country that issued the visa and departing to a third Country
So no, you do not need a visa