wi fi – Understanding the 802.11 frame structure and Android probe request different?


I have read here and on Google a lot about the 802.11 Frames
but something doesn’t add up.

can it be that there is a different between Android 8 and Android 5.1?
the request is not the same? or maybe it sent some random MAC ?

because when I “sniff ” android 5.1 device – I can see it “on the air” while when I “sniff” – android 8 device , I don’t see it

(I know the MAC of both devices I’m searching )

Thanks ,