Perhaps you should try some spelling variations:
"tinh khung luan van thien hoat" » "trinh khung luan van thien hoat", "tinh hung luan van thien hoat", "tinh khang luan van thien hoat", "tinh chung luan van thien hoat", "tinh hang luan van thien hoat", "tinh hung tuan van thien hoat", "tinh khung luan van trien hoat", "tinh khung luan van thien thuat", "tinh khung luan van tien hoa", "tinh khung luan van tien hoat", "tinh khung luan van hien hoat", "tinh khung luan van chien hoat"
"trinh dung luan hoan hieu qua" » "trinh dung luan hoan thien qua", "trinh dung luan hoang dieu qua", "trinh dung luan doanh hieu qua"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("trinh dung luan hoan hieu qua") or ("tinh khung luan van thien hoat"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("trinh dung luan hoan hieu qua") OR ("tinh khung luan van thien hoat"))*.
• Removing quotes may allow a broader search: (( trinh dung luan hoan hieu qua ) or ( tinh khung luan van thien hoat ))*.