Perhaps you should try some spelling variations:
nhung phuong » dung phuong, nhu phuong, truong phuong
hieu quang » thieu quang, hieu quan, hieu qua
thanh tung » thanh cong
trinh toan » tinh toan, thanh toan, trinh han
cua nhung » va nhung
hinh toan » tinh toan, thanh toan, manh toan
doc hieu » toc thieu, hoc thieu, hoc hien

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 - ((thanh trung) OR (thanh tung)) cua nhung phuong ((hinh toan) or (trinh toan)) tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu quang - ((thanh trung) OR (thanh tung)) cua nhung phuong ((hinh toan) OR (trinh toan)) tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu quang - ((thanh trung) OR (thanh tung)) cua nhung phuong ((hinh toan) or (trinh toan)) tap".
• Adding a wildcard symbol may retrieve word variants: doc hieu quang - ((thanh trung) OR (thanh tung)) cua nhung phuong ((hinh toan) or (trinh toan)) tap*.