Perhaps you should try some spelling variations:
theo chieu » theo tieu, ho chieu, theo chu
chieu sach » chinh sach, chiet tach, chieu sang
nhung cong » dung cong, thong cong, hang cong
trinh vin » trinh van, trinh tin, trinh ven
trinh vi » trinh va, trinh ve, trinh viet
cong tap » cuong tap, cong tac, cong tan
toan cao » toan tap
toan ban » van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo chieu sach - hanh ((trinh vi) or (trinh vin)) nhung cong tap ((toan cao) OR (toan ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo chieu sach - hanh ((trinh vi) OR (trinh vin)) nhung cong tap ((toan cao) OR (toan ban)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo chieu sach - hanh ((trinh vi) or (trinh vin)) nhung cong tap ((toan cao) OR (toan ban))".
• Adding a wildcard symbol may retrieve word variants: theo chieu sach - hanh ((trinh vi) or (trinh vin)) nhung cong tap ((toan cao) OR (toan ban))*.