Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
mang thong » mang trong, hang thuong, dang thuong
hieu lang » chieu sang, hieu quang, nhieu tang
tinh quan » tinh quang, trinh quan, tin quan
thong tan » thong than, thong tran, thong tin
quan lua » quan luan, quan cua, quang cua
lua mang » cua mang, lua sang, qua mang
tran van » luan van

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc ((hieu lang) or (chieu sach)) - tinh quan lua mang thong tan tran van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu lang) OR (chieu sach)) - tinh quan lua mang thong tan tran van.
• Adding a wildcard symbol may retrieve word variants: doc ((hieu lang) or (chieu sach)) - tinh quan lua mang thong tan tran van*.