Perhaps you should try some spelling variations:
nghien thieu » nghiep hieu, nghiep tieu, nguyen thien
nganh khoa » nganh hoa, nganh khong, doanh khoa
sach hoi » sach doi, sach moi, cach thoi
khoa hoc » hoa hoc
hang tai » hang va, dung tai
su sach » so sach, vu sach
hoi tap » hoi dap, hoc tap, hoi tai
mot hoc » mo hoc, mot goc, bot hoc
mon hoc » toan hoc, dong hoc
va hang » van hang, va nang, va lang
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: su sach hoi tap, nghien thieu ((mot hoc) or (mon hoc)) nganh khoa hoc ma hoi va hang tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach hoi tap, nghien thieu ((mot hoc) OR (mon hoc)) nganh khoa hoc ma hoi va hang tai.
• Adding a wildcard symbol may retrieve word variants: su sach hoi tap, nghien thieu ((mot hoc) or (mon hoc)) nganh khoa hoc ma hoi va hang tai*.