Perhaps you should try some spelling variations:
thieu sang » thieu khang, thieu quang, hieu lang
chieu sang » chieu sach, chieu xanh, hieu lang
thong cong » trong cong, tong cong, thong thong
trung cap » truong cao, trung tam
cong vang » cong lang, cong quang, cong ngang
vang phan » van phan, nang phan, quang phan
thong tu » phong tuc, thong tin, thong ke
phan cau » phan dau, phan cac, phan tu

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 sang)) - hanh ((thong tu) or (trung cap)) thong cong vang phan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sang) OR (chieu sang)) - hanh ((thong tu) OR (trung cap)) thong cong vang phan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sang) OR (chieu sang)) - hanh ((thong tu) or (trung cap)) thong cong vang phan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sang) OR (chieu sang)) - hanh ((thong tu) or (trung cap)) thong cong vang phan cau*.