Perhaps you should try some spelling variations:
thuat mach » thuat sach, thuat tach, thuyet mach
mach hoc » cach hoc, dich hoc, anh hoc
cuu dong » cuu cong, cuu tong, cuu long
dong hoc » dong co, dong luc
hoc danh » hoc dan, hoc anh, hoc hanh
danh hoa » thanh hoa, khanh hoa, nganh hoa
danh von » danh ngon, doanh van, danh vinh
lai hoa » dai hoa, loai hoc
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: thuat mach hoc tap, nghien cuu dong hoc danh hoa hoc ((ma hoi) or (lai hoa)) danh von tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat mach hoc tap, nghien cuu dong hoc danh hoa hoc ((ma hoi) OR (lai hoa)) danh von tai.
• Adding a wildcard symbol may retrieve word variants: thuat mach hoc tap, nghien cuu dong hoc danh hoa hoc ((ma hoi) or (lai hoa)) danh von tai*.