Perhaps you should try some spelling variations:
thieu khang » thieu quang
chieu khong » chien chong, chu khong, chieu duong
chieu sang » chieu sach, chieu xanh, hieu lang
thanh tung » thanh cong
cua thong » cua thuong, cua khong, cua tong
thong dan » thong van, tuong dan, thong den
tung cua » trung cua, tuong cua, dung cua
dan toan » van toan, dan than, manh toan
toan cau » toan cao, toan ban, toan tap

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((((thieu khang) OR (chieu khong))) OR (chieu sang)) - thanh tung cua thong thong dan toan cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((((thieu khang) OR (chieu khong))) or (chieu sang)) - thanh tung cua thong thong dan toan cau~".
• Adding a wildcard symbol may retrieve word variants: hoc ((((thieu khang) OR (chieu khong))) or (chieu sang)) - thanh tung cua thong thong dan toan cau*.