Perhaps you should try some spelling variations:
"chien luoc doanh doanh luan van" » "chien luoc toan doanh luan van", "chien luoc doanh hoan luan van", "chien luoc doanh thanh luan van", "chien luoc danh doanh luan van", "chien luat doanh doanh luan van", "chien luoc dinh doanh luan van"
"chien luoi tinh doanh nhan van" » "chien cuoc tinh doanh nhan van", "hien loi tinh doanh nhan van", "chien luoi kinh doanh nhan van", "chien luoi minh doanh nhan van", "chien luoi chinh doanh nhan van", "chien hoi tinh doanh nhan van", "chien loc tinh doanh nhan van", "chien gioi tinh doanh nhan van", "chien luoi tinh doanh nhan dan", "chien luoi tinh doanh nhan va", "chien luoi tinh doanh phan van"

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("chien luoi tinh doanh nhan van") or ("chien luoc doanh doanh luan van"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("chien luoi tinh doanh nhan van") OR ("chien luoc doanh doanh luan van")).
• Removing quotes may allow a broader search: (( chien luoi tinh doanh nhan van ) or ( chien luoc doanh doanh luan van )).
• Adding a wildcard symbol may retrieve word variants: (("chien luoi tinh doanh nhan van") or ("chien luoc doanh doanh luan van"))*.