Perhaps you should try some spelling variations:
trinh thiet » trinh viet, trinh thi
nghiem dau » nghiep dau, nghiem va, nghiem ban
sach trinh » sach tranh, hanh trinh, sach kinh
nghiem du » nghiem d, nghiem de, nghiem do
thiet dai » thiet hai, thuyet dai, hien dai
toc pham » tac pham, toc cham, toi pham
pham tai » pham thi, pham van
tu sach » thu sach, su sach, te sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( toc pham tai ((nghiem du) OR (nghiem dau)) hoc ) or ( tu sach trinh thiet dai hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( toc pham tai ((nghiem du) OR (nghiem dau)) hoc ) OR ( tu sach trinh thiet dai hoc )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( toc pham tai ((nghiem du) OR (nghiem dau)) hoc ) or ( tu sach trinh thiet dai hoc ))".
• Adding a wildcard symbol may retrieve word variants: (( toc pham tai ((nghiem du) OR (nghiem dau)) hoc ) or ( tu sach trinh thiet dai hoc ))*.