Perhaps you should try some spelling variations:
cong thanh » dong thanh, cong trinh, truong thanh
hoc thiet » hoc thieu, hoc thuyet, hoc hien
tao thiet » tai thiet, tay thiet, toan thiet
hanh tran » hanh trang, thanh tran, hanh tram
tran van » luan van
van dung » van dong, xay dung, tin dung
cong tan » cong tac, cong san, cong ty
tran ban » tranh ban, toan ban, tran bai

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc thiet) or (tao thiet)) tach - hanh tran van dung ((cong tan) OR (cong thanh)) tran ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc thiet) OR (tao thiet)) tach - hanh tran van dung ((cong tan) OR (cong thanh)) tran ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc thiet) or (tao thiet)) tach - hanh tran van dung ((cong tan) OR (cong thanh)) tran ban".
• Adding a wildcard symbol may retrieve word variants: ((hoc thiet) or (tao thiet)) tach - hanh tran van dung ((cong tan) OR (cong thanh)) tran ban*.