Perhaps you should try some spelling variations:
khong thuoc » khang thuoc, hong phuoc, dong thuoc
nhanh khong » nhanh chong, nganh khong, nhan khong
hoc nhanh » hoc nganh, hoc phan
cuu toan » cuu hoan, cua toan, huu toan
toan hoc » toan khoa, van hoc, hoa hoc
thuoc ma » hoc ma, duoc ma
nhan dan » phan dau, gian dan, nhan tai
tu mach » tu cach, tu hach, tu sach
tu manh » tu minh, tu hanh, vu manh
ma hoi » mai hoi, xa hoi, ma hoa
hoi ca » hoi cua, hoi cac, hoi cau

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 manh)) hoc tap, nghien cuu toan hoc nhanh khong thuoc ma hoi ca nhan dan~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu mach) OR (tu manh)) hoc tap, nghien cuu toan hoc nhanh khong thuoc ma hoi ca nhan dan".
• Adding a wildcard symbol may retrieve word variants: ((tu mach) OR (tu manh)) hoc tap, nghien cuu toan hoc nhanh khong thuoc ma hoi ca nhan dan*.