There's a reporter on NPR who sounds like he always introduces himself as "han zhi lu wong". I say that to google voice search, and it corrects it to "Hansi Lo Wang".
So google voice recognition works even if you don't know what words you're saying!
e.g. with your example, the letter pair ‘si’ is pronounced differently in Mandarin that it is in English. So it's not surprising that you couldn't write it down properly in pinyin as you don't know how to transcribe Mandarin into pinyin. But Google does.
Another example - without knowing how French spelling works there is no way that as an English speaker you could work out how to correctly spell ‘peut’ (can) just from hearing it.
Now Google recognizes I'm talking about Minot but it says Minnow back to me.
If you both have learned the word, who is better at recognizing it? And who is better at learning a new word they don't know? These aren't very exacting questions because the comparison between human and machine knowing and learning hasn't been defined. Maybe the machine needs more examples and more contexts to learn a word as well as a human and correctly map to the word as often as a human, but it can also examine more examples and contexts than a human can per unit time and can do a lot of scaling in this regard using increased energy that a human cannot.
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That seems really unlikely to ever happen. Note that by default Google stores the audio of your searches - including the few seconds before you said "ok google" - indefinitely: https://history.google.com/history/audio