Perhaps you should try some spelling variations:
cong thuoc » cong thuc, dong thuoc, cong thuong
long thuoc » luong thuoc, dong thuoc, khong thuoc
hoc thanh » hoc nhanh, hoan thanh, hoc phan
toc sach » hoc sach, doc sach, thuoc sach
sach hoc » cach hoc, sach hoi, mach hoc
phap vat » phap luat, phap phat, phap viet
cuu mon » cuu mo, cuu mot, cuu cong
mon hoc » toan hoc, dong hoc
va phap » va phat, ban phap
va hoi » xa hoi, va hoc, va hoa

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: toc sach hoc tap, nghien cuu mon hoc thanh ((cong thuoc) OR (long thuoc)) va hoi va phap vat~.
• Adding a wildcard symbol may retrieve word variants: toc sach hoc tap, nghien cuu mon hoc thanh ((cong thuoc) or (long thuoc)) va hoi va phap vat*.