Perhaps you should try some spelling variations:
nhung phuong » dung phuong, nhu phuong, truong phuong
phuong tinh » phuong trinh, phuong binh, khuong tinh
hieu quang » thieu quang, hieu quan, hieu qua
hieu lang » chieu sang, nhieu tang, hieu van
trang cua » tranh cua, tang cua, trung cua
mang cua » manh cua, dung cua, ban cua
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: doi ((hieu lang) OR (hieu quang)) - hanh ((trang cua) or (mang cua)) nhung phuong tinh toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi ((hieu lang) OR (hieu quang)) - hanh ((trang cua) OR (mang cua)) nhung phuong tinh toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi ((hieu lang) OR (hieu quang)) - hanh ((trang cua) or (mang cua)) nhung phuong tinh toan ban".
• Adding a wildcard symbol may retrieve word variants: doi ((hieu lang) OR (hieu quang)) - hanh ((trang cua) or (mang cua)) nhung phuong tinh toan ban*.