First and foremost, I would like to thank God, because without His guidance, the completion of my master's degree would not have been possible. God is always my strength and gives me the discipline to help me maintain patience during this hard process. I would like to thank my family for their support, understanding, and encouragement. Their overwhelming love and constant support have been the driving force in the completion of my master's degree. My appreciation cannot be fully expressed in words. I love my family so much. I would like to express my deepest appreciation to my advisor, Dr. Linda Niehm. Without her insightful advice and her devotion of time, I would not have successfully completed this study. She is a great scholar and mentor to me. I would also like to thank my committee members, Dr. Jessica Hurst and Dr. E. Kwan Choi, for their helpful suggestions and encouragement to improve my thesis. I would like to extend my thanks to many of my Vietnamese friends and my uncle who helped me to collect data, especially my friends Long Pham, Tran Quang Quynh Tran, Tam Do Thi, Thanh Thi Huynh, and my uncle Pil Soo Cho. Finally, I would like to thank all people who participated in this project, because without you, I would not have been able to complete my research. I truly am grateful for your time, insights, thoughtfulness, and openness.