A copy of the phone, what's the difference??

Question

Mobile devices

Please explain how samsung differs from Samsung copy "Vietnamese", I ask this question, because in google for this request "recommendations And tips" were issued on how to distinguish the original from the "copy".
I give the full alignment: (I live in Turkmenistan, Ashgabat)
In our stores, for example, a phone costs 7500 manats (redmi note 9 pro), but there is also a "Vietnamese copy" and it already costs 2300 manats. I am already silent about samsung s21/s20+/s20, which cost more than 20,000 manats, but the same "copy" also costs 2300. What is the difference between a copy and an original? Maybe in the "insides" of the device, that is, if I buy this copy, will I have other "unforeseen" problems?

Answer 1

They already said it right in the comment, I'll decipher it.
It's like adidas or abibas sneakers... a copy is not a Samsung phone, but something made by the Chinese and xs what's inside and how it generally works.
Example - the original has an adequate camera, display, 4GB of RAM and 16GB of memory.
A copy may well have - a 0.3mp camera, a display from a Soviet TV, 1GB of RAM and 4-8GB of memory ...
Something like that)