Perhaps you should try some spelling variations:
thieu sang » chieu sang, thieu khang, thieu quang
chieu sach » chinh sach, chiet tach, chieu sang
hanh dinh » thanh dinh, hinh dinh, hanh tinh
dung cong » dung trong
dinh vat » sinh vat, dinh van, dinh dat
vat dung » van dung, va dung, viet dung
tac toan » tam toan, hach toan, tich toan
tap toan » tap doan, tap quan, bai toan

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) or (chieu sach)) - hanh dinh vat dung cong ((tac toan) OR (tap toan)) tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sang) OR (chieu sach)) - hanh dinh vat dung cong ((tac toan) OR (tap toan)) tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sang) or (chieu sach)) - hanh dinh vat dung cong ((tac toan) OR (tap toan)) tap".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sang) or (chieu sach)) - hanh dinh vat dung cong ((tac toan) OR (tap toan)) tap*.