First, read the English article below.

Not everyone needs a visa to visit Canada. For instance, United States citizens do not need a visa. Visit the Government of Canada's website at http://www.cic.gc.ca/english/visit/visas.asp, which has a section titled "Find out if you need a visa." Find your country in the drop-down list, and then answer any other questions that pop up. Once you hit "Go," it will tell you whether or not you need a visa. Note that whether you need a visa or not, you will need a valid passport to enter Canada. Canada is also implementing another type of travel authorization, which will be made final in March 2016. It's called an Electronic Travel Authorization (eTA) and only applies to people entering the country by air from certain countries. For instance, if you are flying from Australia, you need this authorization. When you search for whether or not you need a visa, it should tell you whether or not you need an ETD instead. One of the most common reason for a visa applications is if you are planning to visit as a tourist. You may also get one for business trips. Finally, you can get a visa to see your kids or grandkids. You may want to apply for a super visa as a parent or grandparent, even if you don't need a visa to visit Canada; this visa lets you visit for as long as 2 years. 

Now, please write a short abstract for it in Vietnamese. Abstract:
Kiểm tra xem bạn có cần xin thị thực vào Canada không. Kiểm tra xem bạn có thể xin thị thực điện tử hay không. Bạn cần có lý do chính đáng để xin thị thực.