Perhaps you should try some spelling variations:
sach dong » sach dung, sach song, sach rong
hoc nganh » hoc nhanh
dong tac » cong tac, dong tai, dong bac
hoc danh » hoc dan, hoc anh, hoc hanh
cua hang » cua dang, cua nhung, cua cong
hang tai » hang va, dung tai
so sach » so sanh, bo sach, co sach
cuu mon » cuu mo, cuu mot, cuu cong
hoi cua » hoi chuc
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: so sach dong tac, nghien cuu mon ((hoc nganh) or (hoc danh)) hoa hoc ma hoi cua hang tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach dong tac, nghien cuu mon ((hoc nganh) OR (hoc danh)) hoa hoc ma hoi cua hang tai.
• Adding a wildcard symbol may retrieve word variants: so sach dong tac, nghien cuu mon ((hoc nganh) or (hoc danh)) hoa hoc ma hoi cua hang tai*.