Translation:All our relatives live in Canada.
Your assumption doesn't pan out though. Looking it up on Google Ngrams, we see that "all our" has always been orders of magnitude more popular than "all of our" but the former has been slowly falling for centuries while the latter has been slowly rising. Until the 2000s when "all our" has suddenly started to regain popularity. The trend is the same for UK and US English too: https://books.google.com/ngrams/graph?content=all+of+our%2Call+ouryear_start=1800year_end=2018corpus=15smoothing=0share=direct_url=t1%3B%2Call%20of%20our%3B%2Cc0%3B.t1%3B%2Call%20our%3B%2Cc0
Both should definitely be accepted of course.
RANDOM BREAKDOWN OF 加拿大 (Canada):
Uses of 加 (jiā) that we learned before:
加 (jiā) = to add
油 (yóu) = oil
加油 (jiāyóu) = to add oil/to cheer sb on
参 (cān) = to participate/to join
加 (jiā) = to add/plus
参加 (cānjiā) = to participate/to join
We didn't see 拿 (ná) in another context, I think.
Uses of 大 (dà) that we learned before:
大 (dà) = big/huge/large
意大利 (yìdàlì) = Italy