The purpose of this study was to investigate a more effective direction of pragmatic education by exploring the process of acquiring speech in the communication experience of Vietnamese language learners. Therefore, the study conducted in-depth interviews with seven Vietnamese language learners. The in-depth interviews focused on the process of pragmatic failure or speech acquisition, which emerged from the learner’s communication experience. The result of the study showed that Vietnamese language learners experienced a variety of pragmatic failures in the process of communication, mainly because of the differences in Korean and Vietnamese speaking norms, their limited Korean language skills, and the impact of their educational content. The experience of failure has led learners to emphasize the need for learning through experience and pragmatic education. Based on these findings, the study suggests the following implications for a more effective Korean language education for Vietnamese learners: Korean language education sites for Vietnamese language learners should consider the differences between the Korean and Vietnamese linguistic norms, and pragmatic learning and teaching by presenting the contexts and circumstances should be performed.