Thank you so much. This made me confused also, so I think it better to include every trips. (even if I do not have stamps in my passport about some trips-to home country, or to the USA) Thanks again!It is not written mate, this is the instruction that causes confusion:
".......List all trips you have take outside your country of origin or residence....."
http://www.cic.gc.ca/english/pdf/kits/forms/IMM5562E.pdf
This too me that means enter all international trips. I think it's better as I see a lot of people getting requests for travel history after submitting their applications.
Regards