Perhaps you should try some spelling variations:
thoi nghiem » thi nghiem, khoi nghiep, thuc nghiem
thuat sach » thuat lanh, thuat san
tam nghiem » trac nghiem, trai nghiem, lam nghiep
tam nghien » lam nghiep, va nghien
cach thoi » cac thoi, cach thuc, cach noi
nghiem de » nghiem d, nghiem do, nghiem te
tu cach » tu cac
de hoc » te hoc, du hoc, dien hoc
d hoc » du hoc, ad hoc, y hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tu cach thoi nghiem de hoc ) or ( thuat sach ((tam nghiem) OR (tam nghien)) d hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu cach thoi nghiem de hoc ) OR ( thuat sach ((tam nghiem) OR (tam nghien)) d hoc )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( tu cach thoi nghiem de hoc ) or ( thuat sach ((tam nghiem) OR (tam nghien)) d hoc ))".
• Adding a wildcard symbol may retrieve word variants: (( tu cach thoi nghiem de hoc ) or ( thuat sach ((tam nghiem) OR (tam nghien)) d hoc ))*.