Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
thong cong » trong cong, tong cong, thong thong
hieu lang » chieu sang, hieu quang, nhieu tang
trang cua » tranh cua, tang cua, thang cua
trung cua » truong cua, trung tuan, trung cap
cong dan » cong san, cong tan, huong dan
dan chan » dan gian, dan ca, van chat
chan ban » can ban, chat ban, chan nan

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)) - hanh ((trang cua) OR (trung cua)) thong cong dan chan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sach) OR (hieu lang)) - hanh ((trang cua) OR (trung cua)) thong cong dan chan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sach) or (hieu lang)) - hanh ((trang cua) OR (trung cua)) thong cong dan chan ban".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sach) or (hieu lang)) - hanh ((trang cua) OR (trung cua)) thong cong dan chan ban*.