Perhaps you should try some spelling variations:
hieu lang » chieu sang, hieu quang, nhieu tang
trong san » trong cac, cong san, dong san
doc hieu » toc thieu, hoc thieu, hoc hien
trung co » trong co, truong cao, trung hoc
trung bo » truong bo, trung hoc, trung hoa
san phu » san pham
phu cau » nhu cau, pha cau, phu can

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 - thanh ((trung co) or (trung bo)) dung trong san phu cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu lang - thanh ((trung co) OR (trung bo)) dung trong san phu cau.
• Adding a wildcard symbol may retrieve word variants: doc hieu lang - thanh ((trung co) or (trung bo)) dung trong san phu cau*.