And your last statement about not being able to rely on the certificate, is that unreliable tests in general or only unreliable certificates due to buying them?

I do understand that the testing can have a different meaning than according to European (or Western) standards. I'm not trying to condemn, absolutely not. I'm just hoping to find out what it would mean for a person who wants to marry, probably not knowing that he or she has a disease, and finding that out through a obliged test.