Perhaps you should try some spelling variations:
"cong trinh luan van ttien cong ha luong" » "cong trinh luat van ttien cong ha luong", "cong trinh quan van ttien cong ha luong", "cong trinh han van ttien cong ha luong", "cong trinh luan van thien cong ha luong", "cong trinh luan van trien cong ha luong", "cong trinh luan van tien cong ha luong", "cong trinh luan van chien cong ha luong", "cong trinh luan van ttien cong hai luong", "cong trinh luan van ttien cong ham luong", "cong trinh luan van ttien cong ha long", "cong trinh luan van ttien cong hoa luong", "cong trinh luan van ttien dong ha luong", "cong trinh luan van ttien cong tac luong"
"cong trinh luan van hien cong cua luong" » "cong trinh luat van hien cong cua luong", "cong trinh quan van hien cong cua luong", "cong trinh han van hien cong cua luong", "cong trinh luan van thien cong cua luong", "cong trinh luan van tien cong cua luong", "cong trinh luan van dien cong cua luong", "cong trinh luan van hien cong cu luong", "cong trinh luan van hien cong cua huong", "cong trinh luan van hien cong chat luong", "cong trinh luan van hieu cong cua luong", "cong trinh luan van hien dong cua luong", "cong trinh luan van hien huong cua luong"

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: (("cong trinh luan van ttien cong ha luong") or ("cong trinh luan van hien cong cua luong"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("cong trinh luan van ttien cong ha luong") OR ("cong trinh luan van hien cong cua luong")).
• Removing quotes may allow a broader search: (( cong trinh luan van ttien cong ha luong ) or ( cong trinh luan van hien cong cua luong )).
• Adding a wildcard symbol may retrieve word variants: (("cong trinh luan van ttien cong ha luong") or ("cong trinh luan van hien cong cua luong"))*.