Perhaps you should try some spelling variations:
phuong thong » phuong trong, thong thong, phuong hoang
chieu sang » chieu sach, chieu xanh, hieu lang
tung quan » tuong quan, trung quan, tong quan
dung quan » dung quang, dung luan, luong quan
thong dan » thong van, tuong dan, thong den
dan khoan » dan khoa, dai khoang, toan khoan
khoan cam » khoa cam, khoan va, phan cam
ho chieu » theo chieu, hoc thieu, mot chieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho chieu sang - thanh ((tung quan) or (dung quan)) phuong thong dan khoan cam~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho chieu sang - thanh ((tung quan) OR (dung quan)) phuong thong dan khoan cam.
• Adding a wildcard symbol may retrieve word variants: ho chieu sang - thanh ((tung quan) or (dung quan)) phuong thong dan khoan cam*.