Perhaps you should try some spelling variations:
nganh khong » nganh cong, nhanh chong, nganh nong
nghien thu » nghiem thuc, nghiep thuc, nghien cuu
sach tong » sach song, sach rong, sach thuong
nganh hoa » thanh hoa, khanh hoa, danh hoa
tong tap » tuong tac, trong tan, cong tac
cong hoc » dong hoc, cong hoa, cong coc
nhan tai » hang tai, van tai, toan tai
tu sach » thu sach, su sach, te sach
va nhan » van nhan, ca nhan, va phan
hoa va » hoa van, hoa xa, hoa vo

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 tong tap, nghien thu cong hoc ((nganh hoa) or (nganh khong)) hoc ma hoa va nhan tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach tong tap, nghien thu cong hoc ((nganh hoa) OR (nganh khong)) hoc ma hoa va nhan tai.
• Adding a wildcard symbol may retrieve word variants: tu sach tong tap, nghien thu cong hoc ((nganh hoa) or (nganh khong)) hoc ma hoa va nhan tai*.