Perhaps you should try some spelling variations:
trung thanh » truong thanh
chieu sang » chieu sach, chieu xanh, hieu lang
khong cong » thong cong, khong cang, chong cong
tran tuan » tran xuan, tran quang, tran thanh
cong danh » cuong danh, cong dan, cong thanh
ho chieu » theo chieu, hoc thieu, doi chieu
toan cao » toan ban
toan tap » toan ban

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ho chieu sang - manh ((trung thanh) OR (tran tuan)) khong cong danh ((toan cao) OR (toan tap))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho chieu sang - manh ((trung thanh) or (tran tuan)) khong cong danh ((toan cao) OR (toan tap))~".
• Adding a wildcard symbol may retrieve word variants: ho chieu sang - manh ((trung thanh) or (tran tuan)) khong cong danh ((toan cao) OR (toan tap))*.