Perhaps you should try some spelling variations:
thiet tach » chiet tach, thien hach, thuat tach
hoc thiet » hoc thieu, hoc thuyet, hoc hien
trung vap » trung cap, trung va, trung lap
trung van » truong van, trong van, trung va
hang cong » dang cong, hang nong, bang cong
thanh cap » thanh lap, than cap, thanh ca
cong san » cong tac
hanh cap » hanh cac, hanh cat, hanh cad

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