The Vietnamese word "đột phá khẩu" translates to "break-through" in English, especially in a military context. It refers to a significant and sudden advance or penetration into an enemy's defensive position, allowing for further progress or exploitation of weaknesses.
While "đột phá khẩu" is primarily military, it can also metaphorically apply to any situation where a significant barrier is overcome. In a broader sense, it can relate to personal achievements or breakthroughs in knowledge.