Perhaps you should try some spelling variations:
"nguyen can minh khai" » "nguyen van minh khai", "nguyen xuan minh khai", "nguyen cong minh khai", "nguyen can minh khue", "nguyen can minh chi", "nguyen can minh pham", "nguyen cao minh khai", "nguyen ban minh khai"
"nguyen chi minh khai" » "nguyen thi minh khai", "nguyen nhu minh khai", "nguyen hai minh khai", "nguyen chi minh khue", "nguyen chi minh chi", "nguyen chi minh pham"
"nguyen chi minh chau" » "nguyen thi minh chau", "nguyen nhu minh chau", "nguyen hai minh chau", "nguyen chi tinh chat"

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 chi minh chau"))) or ("nguyen can minh khai"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("nguyen chi minh khai") OR ("nguyen chi minh chau"))) OR ("nguyen can minh khai")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"nguyen chi minh khai\") OR (\"nguyen chi minh chau\"))) or (\"nguyen can minh khai\"))".
• Removing quotes may allow a broader search: (((( nguyen chi minh khai ) OR ( nguyen chi minh chau ))) or ( nguyen can minh khai )).
• Adding a wildcard symbol may retrieve word variants: (((("nguyen chi minh khai") OR ("nguyen chi minh chau"))) or ("nguyen can minh khai"))*.