Perhaps you should try some spelling variations:
"chieu scientific officer" » "hieu scientific officer", "chien scientific officer", "nhieu scientific officer", "chieu scientific officers", "chieu scientific offices"
"chieu scientific office" » "hieu scientific office", "chien scientific office", "nhieu scientific office"
"thieu scientific office" » "hieu scientific office"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("chieu scientific officer") or ((("chieu scientific office") OR ("thieu scientific office"))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("chieu scientific officer") OR ((("chieu scientific office") OR ("thieu scientific office")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"chieu scientific officer\") or (((\"chieu scientific office\") OR (\"thieu scientific office\"))))".
• Removing quotes may allow a broader search: (( chieu scientific officer ) or ((( chieu scientific office ) OR ( thieu scientific office )))).
• Adding a wildcard symbol may retrieve word variants: (("chieu scientific officer") or ((("chieu scientific office") OR ("thieu scientific office"))))*.