Perhaps you should try some spelling variations:
thieu quang » hieu quang, thien quan, trien quang
thieu sang » chieu sang, thieu khang, hieu lang
trinh toan » tinh toan, thanh toan, trinh han
lang cong » dang cong, bang cong, hang cong
tuong va » truong va, thuong va, luong va
toan cao » toan ban, toan tap
tung va » trung va, dung va, vung va

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 (thieu quang)) - thanh ((tung va) or (tuong va)) lang cong trinh toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sang) OR (thieu quang)) - thanh ((tung va) OR (tuong va)) lang cong trinh toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sang) OR (thieu quang)) - thanh ((tung va) or (tuong va)) lang cong trinh toan cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sang) OR (thieu quang)) - thanh ((tung va) or (tuong va)) lang cong trinh toan cao*.