Perhaps you should try some spelling variations:
chieu xanh » chieu sach, chieu sang, chieu tinh
trung cong » truong cong, trong cong, trung uong
hanh tang » hanh trang, anh tang, hanh tung
hanh mang » nhanh mang, hanh trang, nhanh lang
cua trung » cua truong, xuan trung, cua nhung
ho chieu » theo chieu, hoc thieu, doi chieu

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 xanh - ((hanh tang) OR (hanh mang)) cua trung cong trinh ((toan ban) OR (van ban))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho chieu xanh - ((hanh tang) or (hanh mang)) cua trung cong trinh ((toan ban) OR (van ban))~".
• Adding a wildcard symbol may retrieve word variants: ho chieu xanh - ((hanh tang) or (hanh mang)) cua trung cong trinh ((toan ban) OR (van ban))*.