A canonical location name is the precise string Google uses to identify a place in its Geotargets dataset — for instance "Surrey,British Columbia,Canada", with commas and no stray spaces. It is the text that gets encoded into a uule.
Precision matters because the name is matched exactly. "Surrey, BC" or "T.O." are not canonical and resolve to nothing. Copy the spelling straight from Google's published Geotargets list before encoding it.
See how Canonical location name changes real results: compare Google from any two locations.