Perhaps you should try some spelling variations:
"nguyen chi minh khai" » "nguyen nhu minh khai", "nguyen hai minh khai", "nguyen thu minh khai", "nguyen chi minh chau", "nguyen chi minh chi", "nguyen chi minh pham"
"nguyen can minh khue" » "nguyen van minh khue", "nguyen xuan minh khue", "nguyen cong minh khue", "nguyen cao minh khue", "nguyen ban minh khue"
"nguyen thi hanh khai" » "nguyen thi manh khai", "nguyen thi nhanh thai", "nguyen thi thanh hai", "nguyen thi thanh khai"

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("nguyen chi minh khai") or ("nguyen can minh khue"))) or ("nguyen thi hanh khai"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("nguyen chi minh khai") OR ("nguyen can minh khue"))) OR ("nguyen thi hanh khai")).
• Removing quotes may allow a broader search: (((( nguyen chi minh khai ) or ( nguyen can minh khue ))) or ( nguyen thi hanh khai )).
• Adding a wildcard symbol may retrieve word variants: (((("nguyen chi minh khai") or ("nguyen can minh khue"))) or ("nguyen thi hanh khai"))*.