Perhaps you should try some spelling variations:
nganh khoa » nganh hoa, nganh khong, doanh khoa
nghien thu » nghiem thuc, nghiep thuc, nghien cuu
hoc nganh » hoc nhanh
nhan tai » hang tai, van tai, toan tai
sach doi » sach hoi, sach moi, sach dao
khoa hoc » hoa hoc
cong hoc » dong hoc, cong hoa, cong coc
voi cac » loi cach
doi tap » doi tac, doi dap, doi tai
nhan va » nhan dan, nhan tao, phan van
te sach » toc sach
hoc da » hoc dan, hoc dai, hoc dat
da voi » dao voi, dua voi, ba voi

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: te sach doi tap, nghien thu cong hoc nganh khoa hoc da voi cac ((nhan va) OR (nhan tai))~.
• Adding a wildcard symbol may retrieve word variants: te sach doi tap, nghien thu cong hoc nganh khoa hoc da voi cac ((nhan va) or (nhan tai))*.