Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
nhung cong » dung cong, thong cong, hang cong
trung cua » truong cua, trung tuan, trung cap
cong tinh » cong trinh, cong vinh, long tinh
doc hieu » toc thieu, hoc thieu, hoc hien
tang cua » mang cua, hang cua, tang luan
toan ban » van ban

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 quang - hanh ((tang cua) or (trung cua)) nhung cong tinh toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu quang - hanh ((tang cua) OR (trung cua)) nhung cong tinh toan ban.
• Adding a wildcard symbol may retrieve word variants: doc hieu quang - hanh ((tang cua) or (trung cua)) nhung cong tinh toan ban*.