Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
nganh khoa » nganh hoa, nganh khong, doanh khoa
hoc nganh » hoc nhanh
toc sach » hoc sach, doc sach, nuoc sach
khoa hoc » hoa hoc
giai dan » giai doan, gian dan, giai han
doi tap » doi tac, doi dap, doi tai
cuu mon » cuu mo, cuu mot, cuu cong
mon hoc » toan hoc, dong 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: ((toc sach) or (thuoc sach)) doi tap, nghien cuu mon hoc nganh khoa hoc ma hoi va giai dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (thuoc sach)) doi tap, nghien cuu mon hoc nganh khoa hoc ma hoi va giai dan.
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (thuoc sach)) doi tap, nghien cuu mon hoc nganh khoa hoc ma hoi va giai dan*.