Perhaps you should try some spelling variations:
nghien cac » nghiep cach, nghien cuu, nghiep cay
hoc nganh » hoc nhanh
nganh hoa » thanh hoa, khanh hoa, danh hoa
sach doi » sach hoi, sach moi, sach dao
cac cong » cua cong
cong hoc » dong hoc, cong hoa, cong coc
phan dau » phan tu, hang dau
su sach » so sach, vu sach
doi tap » doi tac, doi dap, doi tai
hoi dan » hoa dan, hoc dan, hoi dap
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 doi tap, nghien cac cong hoc nganh hoa hoc ma hoi dan ((phan dau) or (dung tai))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach doi tap, nghien cac cong hoc nganh hoa hoc ma hoi dan ((phan dau) OR (dung tai)).
• Adding a wildcard symbol may retrieve word variants: su sach doi tap, nghien cac cong hoc nganh hoa hoc ma hoi dan ((phan dau) or (dung tai))*.