Perhaps you should try some spelling variations:
thieu quang » hieu quang, thien quan, trien quang
thieu sang » chieu sang, thieu khang, hieu lang
thanh tung » thanh cong
chong cong » cong cong, thong cong, cuong cong
cang thang » cong thanh, dang thanh
cap chong » phap chong, chat chong, chap phong
sang than » dang thanh, sang tao, ban than
tung cap » trung cap, cung cap, thong cap

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