Perhaps you should try some spelling variations:
thieu sang » chieu sang, thieu khang, thieu quang
thanh tung » thanh cong
hoc thieu » toc thieu, hoc hien
vat khong » va khong, vat khoa, vat trong
cong lang » cong luong, cong quang, cong ngang
cong vang » cong quang, cong ngang, cong san
tung vat » dung vat, tang vat, tung va
than cau » phan cau, than cap, thanh chau
toan cau » 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 thieu sang - thanh tung vat khong ((cong lang) or (cong vang)) ((than cau) or (toan cau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sang - thanh tung vat khong ((cong lang) OR (cong vang)) ((than cau) OR (toan cau)).
• Adding a wildcard symbol may retrieve word variants: hoc thieu sang - thanh tung vat khong ((cong lang) or (cong vang)) ((than cau) or (toan cau))*.