Perhaps you should try some spelling variations:
trinh trong » trinh truong, tranh trong, trinh trung
chieu sach » chinh sach, chiet tach, chieu sang
hieu lang » chieu sang, hieu quang, nhieu tang
trong con » trong cong, trong co, trong can
dung cong » dung trong
con dung » con duong, cong dung, con rung
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 ((chieu sach) or (hieu lang)) - trinh trong con dung cong dan van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sach) OR (hieu lang)) - trinh trong con dung cong dan van ban.
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sach) or (hieu lang)) - trinh trong con dung cong dan van ban*.