Perhaps you should try some spelling variations:
"su canh tranh cong khi đong luc" » "su canh thanh cong khi đong luc", "su canh trinh cong khi đong luc", "su canh tran cong khi đong luc", "su canh tranh cong thai đong luc", "su canh tranh co khi đong luc", "su canh tranh cong ha đong luc", "suc canh tranh cong khi đong luc", "su can tranh cong khi đong luc", "su anh tranh cong khi đong luc"
"su sach ngan khong khi đong luc" » "su sach nganh khong khi đong luc", "su sach nhan khong khi đong luc", "su sach ngan hang khi đong luc", "su sach ngon khong khi đong luc", "su sach nha khong khi đong luc", "su sach han khong khi đong luc", "su sach ngan khong he đong luc", "so sach ngan khong khi đong luc", "vu sach ngan khong khi đong luc"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("su canh tranh cong khi đong luc") or ("su sach ngan khong khi đong luc"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("su canh tranh cong khi đong luc") OR ("su sach ngan khong khi đong luc"))*.
• Removing quotes may allow a broader search: (( su canh tranh cong khi đong luc ) or ( su sach ngan khong khi đong luc ))*.