For Vietnamese overseas, their opinion and views can be very different with Vietnamese in Vietnam, so when you ask Vietnamese people I guess you are talking about Vietnamese living in Vietnam. About the question how Vietnamese (live in Vietnam) think of Russia and Russian:
For the majority of Vietnamese people, Russia and Russian is respected. For obvious reason. Anyone saying it’s because government propaganda then you bet they’re lying, because it’s completely not true, the Vietnamese media almost always have a neutral stance to everything relates to foreign countries, the only exception would be matters relates to China but only problem related to the East Sea - SCS. If you are talking about education, we were teach that was USSR and socialist nations that help us not just Russia, of course Russia is the direct successor of USSR, that’s why we respect them. Look at Cuba, we respect them too, they didn’t give us billions of dollars and bazillions tons of weapons and ammunition, but their spirit is with us and for us that’s more than enough.
About the Nga Ngố - silly/dumb Russia thing, unlike Vietnamese overseas imagine, it’s not something Vietnamese netizen use because they look down on Russia, it’s just part of the joking attitude of Vietnamese netizen in general. Like calling ourselves “East Laos” - “Đông Lào” or Vịt (Duck), or calling America - Mẽo (literally have no meaning) - or Tạp chủng quốc Hoa Kỳ (Hybrid/Bastard state of America), or United Nations = Ô hợp quốc (Unorganized Nation)
But then you have some Vietnamese who really love USA and hate Russia, then I tell you why.
Vietnamese new generation mostly learn English for work and education, and with the internet boom, they have unlimited access to information on the internet. But due to their young age and lack of knowledge about history and politics they easily accept what the internet feed them. Of course, I know USSR is no saint, but they are far from any evil that imperialist and colonist nations that ever was. Imagine people watching youtube for history lesson, how wrong can it be. If the propaganda do not direct at Vietnam and Vietnamese people, people usually not try to look further than what they got because even if they like Russia, it’s not on the same level as their love for our country. And content in Russian simply unreadable.
The politics during cold war is incredible complicate, it’s quite easy to picking some events to draw a completely different picture. For example Vietnam, China and USSR used to racing for normalization with US, so which one betrayed socialism? US attack Vietnam, Vietnam attack Cambodia, China attack Vietnam, USSR attack Afghanistan, which one is the act of hegemony, which one is not? The answer is always very very complicate. History is like huge jigsaw puzzle, if you don’t have every single pieces to look at the whole picture, a few event can easily mislead you. And the school can’t possible teach you about everything. Even defending Vietnamese history from all those disinformation campaign from US is hard enough. Only recently we see a more neutral view toward Vietnam from western media, and that’s only because (in my opinion) of their “Pivot to Asia” policy, now China is the main focus, so Vietnam - a China’s old wound is naturally drawing their attention. So you can imagine how much bad stuffs Western propaganda throw at countries like “Russia” and “China”.