O que significa And I wondered, what made my dreams so easy to dismiss? Granted, my dreams are shy, becasue they're Canadian.(Laughter) ?

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(Edited the answer below – I was looking through questions from Japanese speakers earlier and originally included Japanese in my response. Since I just noticed you're native language is Korean, I removed the Japanese. Sorry if that caused any confusion!)

Canadian can mean something from or of Canada or it can simply mean a person from Canada.

In this case, I think the speaker is probably a Canadian and since they are Canadian, any dreams they have are also Canadian.

What is funny here is that Canadians are often described as being extremely polite and afraid of offending people. That is, they are portrayed as timid. For example, in America, a joke about Canadians is that they will apologize for anything, even if they aren't at fault.

So since the speaker's dreams are Canadian, their dreams also too timid - and this is inherently because the dreams are Canadian.