Perhaps you should try some spelling variations:
nghien thu » nghiem thuc, nghiep thuc, nghien cuu
nganh khoa » nganh hoa, nganh khong, doanh khoa
hoc nganh » hoc nhanh
cong hoc » dong hoc, cong hoa, cong coc
khoa hoc » hoa hoc
hang dau » hang va, hang tai
tu sach » thu sach, su sach, te sach
toi tap » toan tap, tong tap, tuoi tai
toi gap » toi gian
va hang » van hang, va nang, va lang
hoa va » hoa van, hoa xa, hoa vo

You may be able to get more results by adjusting your search query.

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