Perhaps you should try some spelling variations:
nganh khong » nganh cong, nhanh chong, nganh nong
nganh khoa » nganh hoa, doanh khoa, anh khoa
hoc sach » hoc sinh, hoc cac, hoc anh
sach doi » sach hoi, sach moi, sach dao
nhan tai » hang tai, van tai, toan tai
doi tap » doi tac, doi dap, doi tai
va nhan » van nhan, ca nhan, va phan
mo hoc » mon hoc, co 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: hoc sach doi tap, nghien cuu mo hoc ((nganh khoa) OR (nganh khong)) hoc ma hoi va nhan tai~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach doi tap, nghien cuu mo hoc ((nganh khoa) OR (nganh khong)) hoc ma hoi va nhan tai".
• Adding a wildcard symbol may retrieve word variants: hoc sach doi tap, nghien cuu mo hoc ((nganh khoa) OR (nganh khong)) hoc ma hoi va nhan tai*.