Perhaps you should try some spelling variations:
dong thuoc » dung thuoc, dang thuoc, don thuoc
nganh dong » nganh cong, nhanh dong, nganh nong
hoc nganh » hoc nhanh
thuoc ma » hoc ma, duoc ma
sach moi » sach doi, sach hoi, bach mai
mon hoc » toan hoc, dong hoc
cuu mon » cuu mo, cuu mot, cuu cong
moi tap » moi tai, toi tap
ca gian » ca giang, ca giao, ca gia
va gian » va gianh, van gian, va giai
tu sach » thu sach, su sach, te sach
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 sach moi tap, nghien cuu mon hoc nganh dong thuoc ma hoi ((ca gian) OR (va gian)) dan~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach moi tap, nghien cuu mon hoc nganh dong thuoc ma hoi ((ca gian) OR (va gian)) dan*".