Some preservationists have uploaded the entire season. Search for "SBS Roommate 2014" and use a browser extension to translate the page to Vietnamese. This is great for downloading.
The magic of Season 1 was the "generation gap" casting. It wasn't just young idols; it was a blend of industry veterans and rising stars. The "Mama" of the House Shin Sung-woo roommate season 1 vietsub
It's always best to check official sources first, as they often provide the highest quality and reliable subtitles. Some preservationists have uploaded the entire season