Perhaps you should try some spelling variations:
nhung huong » nhung phuong, nhung tuong, nhung cong
trinh toan » tinh toan, thanh toan, trinh han
trinh tin » trinh kinh, trinh tu, trinh han
duong cao » duong co, duong dao, luong cao
dung cao » dung cho, dung co, dung cac
dan van » dang van, doan van, dao van

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi ((trinh tin) OR (trinh toan)) - thanh ((dung cao) or (duong cao)) nhung huong dan van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi ((trinh tin) OR (trinh toan)) - thanh ((dung cao) OR (duong cao)) nhung huong dan van ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi ((trinh tin) OR (trinh toan)) - thanh ((dung cao) or (duong cao)) nhung huong dan van ban".
• Adding a wildcard symbol may retrieve word variants: doi ((trinh tin) OR (trinh toan)) - thanh ((dung cao) or (duong cao)) nhung huong dan van ban*.