There's no such thing as "the top Google result", Google's search algorithms don't serve up the same results for every search for everyone at every time.
My search results were what I'd expect:
My search results were what I'd expect:
https://stackoverflow.com/tour/documentation
https://stackoverflow.com/documentation/documentation/topics
https://stackoverflow.com/documentation/python/topics
None of these are https://stackoverflow.com/documentation .