Perhaps you should try some spelling variations:
ngang thanh » nang thanh, nganh thanh, ngan thanh
chieu sang » chieu sach, chieu xanh, hieu lang
cong ngang » cong nhan, cong quang, cong lang
hoc chieu » hoc thieu, ho chieu, hoc hien
trong nam » trong lam, trong cac, trong nha
thong nam » thong xay, dong nam, thong va
dung cong » dung trong
thanh mau » hanh mau, thanh san, thanh hai

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 ((trong nam) or (thong nam)) dung cong ngang thanh mau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc chieu sang - hanh ((trong nam) OR (thong nam)) dung cong ngang thanh mau.
• Adding a wildcard symbol may retrieve word variants: hoc chieu sang - hanh ((trong nam) or (thong nam)) dung cong ngang thanh mau*.