It looks like you're looking for the Vietnamese-dubbed or "thuyết minh" version of (1988).
If you specifically want the nostalgic "thuyet minh" experience from old VHS days, search YouTube first, then check the Vietnamese piracy sites as a last resort – but be very careful with your device security. phim rambo 3 thuyet minh
Would you like links to legal streaming services in Vietnam, or help finding subtitles instead? It looks like you're looking for the Vietnamese-dubbed