Perhaps you should try some spelling variations:
trinh thiet » trinh viet
trinh thuat » trinh luat, trinh thuc, trinh chat
trinh thi » trinh tai, dinh thi, trinh tu
hang cong » dang cong, hang nong, bang cong
hoc vien » hoc hien, hoc viet, hoc tieng
cong dan » cong san, cong tan, huong dan
dan van » dang van, doan van, dao van

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

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