Perhaps you should try some spelling variations:
thieu sang » chieu sang, thieu khang, thieu quang
dung thanh » duong thanh, dong thanh, dang thanh
hoc thieu » toc thieu, hoc hien
trinh vat » trinh van, trinh luat, sinh vat
trinh va » trinh van, trinh ve, trinh vi
toan cao » toan ban
toan tap » toan ban

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 sang - canh ((trinh va) OR (trinh vat)) ung dung thanh ((toan cao) OR (toan tap))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu sang - canh ((trinh va) or (trinh vat)) ung dung thanh ((toan cao) OR (toan tap))~".
• Adding a wildcard symbol may retrieve word variants: hoc thieu sang - canh ((trinh va) or (trinh vat)) ung dung thanh ((toan cao) OR (toan tap))*.