Perhaps you should try some spelling variations:
duong manh » duong van
chieu sang » chieu sach, chieu xanh, hieu lang
hoc chieu » hoc thieu, ho chieu, hoc hien
hanh dang » hanh dong, hanh dung, hanh mang
cong manh » cong danh, cong thanh, hoang manh
anh dang » anh dong, anh dung, anh bang
cua dung » cua dang, cua dong, qua dung
toan cao » toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc chieu sang - ((hanh dang) or (anh dang)) cua dung ((cong manh) OR (duong manh)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc chieu sang - ((hanh dang) OR (anh dang)) cua dung ((cong manh) OR (duong manh)) toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc chieu sang - ((hanh dang) or (anh dang)) cua dung ((cong manh) OR (duong manh)) toan cao".
• Adding a wildcard symbol may retrieve word variants: hoc chieu sang - ((hanh dang) or (anh dang)) cua dung ((cong manh) OR (duong manh)) toan cao*.