Perhaps you should try some spelling variations:
trinh dinh » trinh kinh, trinh sinh, trinh dung
hieu lang » chieu sang, hieu quang, nhieu tang
chu trong » chu trang, cay trong, tu trong
hieu van » hieu va, thien van, lieu va
dinh chu » dinh chuc, dinh chau, dinh chua
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: theo ((hieu lang) or (hieu van)) - trinh dinh chu trong cong dan van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((hieu lang) OR (hieu van)) - trinh dinh chu trong cong dan van ban*.