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