Perhaps you should try some spelling variations:
trinh thuat » trinh luat, trinh thiet, trinh chat
chieu sach » chinh sach, chiet tach, chieu sang
trinh thuc » trinh tu, trinh thi
doi chieu » doc hieu, doi chi, ho chieu
cong vang » cong lang, cong quang, cong ngang
cong van » cong san, song van, cong tan
phan cau » phan dau, phan cac, phan tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi chieu sach - hanh ((trinh thuat) OR (trinh thuc)) dung ((cong van) or (cong vang)) phan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi chieu sach - hanh ((trinh thuat) OR (trinh thuc)) dung ((cong van) OR (cong vang)) phan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi chieu sach - hanh ((trinh thuat) OR (trinh thuc)) dung ((cong van) or (cong vang)) phan cau".
• Adding a wildcard symbol may retrieve word variants: doi chieu sach - hanh ((trinh thuat) OR (trinh thuc)) dung ((cong van) or (cong vang)) phan cau*.