Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
thi nghiem » thuc nghiem
tai nghiep » mai nghiep, tac nghiep, trai nghiem
nghiep van » nghiep va, nghiem van, nghiep can
sach thi » sach thu, sach thieu, sach tham
sach tai » sach bai, sach tham, sach dao
su sach » so sach, vu sach
van hoc » van hoa
d hoc » du hoc, de 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: (( thuat sach thi nghiem ((d hoc) OR (ad hoc)) ) or ( su sach tai nghiep van hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( thuat sach thi nghiem ((d hoc) OR (ad hoc)) ) OR ( su sach tai nghiep van hoc )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( thuat sach thi nghiem ((d hoc) OR (ad hoc)) ) or ( su sach tai nghiep van hoc ))".
• Adding a wildcard symbol may retrieve word variants: (( thuat sach thi nghiem ((d hoc) OR (ad hoc)) ) or ( su sach tai nghiep van hoc ))*.