I tried to verify, and I found that "naz" indeed means something like "coquetry" in Farsi, and "be" or "beh" means "good" (albeit not "best", that would be "behtærin" as far as I understand, all transliterated, of course).
But if people here forgive me a little speculating: "good coquetry" as meaning of a name really looks like so much folk etymology to me, and the true etymology of the name could well be something completely different.
Rene
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