Perhaps you should try some spelling variations:
nhung phuong » dung phuong, nhu phuong, truong phuong
phuong trinh » chuong trinh, cong trinh, huong tran
chieu sang » chieu sach, chieu xanh, nhieu tang
thanh tung » thanh cong
trinh toan » tinh toan, thanh toan, trinh han
hieu lang » hieu quang, nhieu tang, hieu van
toan ban » van ban
tung va » trung va, tuong va, dung va

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((chieu sang) OR (hieu lang)) - thanh tung va nhung phuong trinh toan ban~".
• Adding a wildcard symbol may retrieve word variants: theo ((chieu sang) OR (hieu lang)) - thanh tung va nhung phuong trinh toan ban*.