Perhaps you should try some spelling variations:
nhung phuong » dung phuong, nhu phuong, truong phuong
phuong hinh » phuong binh, phuong linh, phuong dinh
chieu sang » chieu sach, chieu xanh, nhieu tang
hieu lang » hieu quang, nhieu tang, hieu van
hinh toan » tinh toan, thanh toan, trinh toan
trang va » hang va
tran van » luan van
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 ((chieu sang) OR (hieu lang)) - canh ((trang va) or (tran van)) nhung phuong hinh toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((chieu sang) OR (hieu lang)) - canh ((trang va) OR (tran van)) nhung phuong hinh toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((chieu sang) OR (hieu lang)) - canh ((trang va) or (tran van)) nhung phuong hinh toan ban".
• Adding a wildcard symbol may retrieve word variants: doc ((chieu sang) OR (hieu lang)) - canh ((trang va) or (tran van)) nhung phuong hinh toan ban*.