Perhaps you should try some spelling variations:
toan thiet » hoan thien, luan thiet, toan tien
hoc thiet » hoc thieu, hoc thuyet, hoc hien
hanh tran » hanh trang, thanh tran, thanh trang
hanh tram » hanh tam, hanh trang, thanh tran
dung cong » dung trong
van dung » van dong, xay dung, tin dung
cong tan » cong tac, cong san, cong thanh
tran ban » tranh ban, tran van, toan ban

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