Perhaps you should try some spelling variations:
cuu dong » cuu cong, cuu tong, cuu long
dong luc » nang luc
luc danh » luoc danh, luc canh, luan danh
danh hoa » thanh hoa, khanh hoa, nganh hoa
gian dan » gian lang
tu mach » tu cach, tu manh, tu sach
tu hach » tu hanh, tu cach, tu sach
va gian » va gianh, van gian, va giai
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu mach) or (tu hach)) hoc tap, nghien cuu dong luc danh hoa hoc ma hoi va gian dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu mach) OR (tu hach)) hoc tap, nghien cuu dong luc danh hoa hoc ma hoi va gian dan.
• Adding a wildcard symbol may retrieve word variants: ((tu mach) or (tu hach)) hoc tap, nghien cuu dong luc danh hoa hoc ma hoi va gian dan*.