Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
nganh cong » nhanh chong, thanh cong
cong thuoc » cong thuc, dong thuoc, long thuoc
hoc nganh » hoc nhanh
thuoc mai » thuoc ma, thuoc tai, thuoc moi
sach hoc » cach hoc, sach hoi, mach hoc
cuu toan » cuu hoan, huu toan, cuu thanh
cua toan » xuan toan, cua thanh, cua doanh
mai khoi » mai khoa, tai khoa, cac khoi
phan van » pham van, thanh van, luan van
khoi va » hoi va, khi va, choi va
va phan » van phan, va phat, va phap

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sach hoc tap, nghien ((cuu toan) or (cua toan)) hoc nganh cong thuoc mai khoi va phan van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach hoc tap, nghien ((cuu toan) OR (cua toan)) hoc nganh cong thuoc mai khoi va phan van.
• Adding a wildcard symbol may retrieve word variants: thuat sach hoc tap, nghien ((cuu toan) or (cua toan)) hoc nganh cong thuoc mai khoi va phan van*.