Perhaps you should try some spelling variations:
thong cong » trong cong, tong cong, thong thong
thieu sang » chieu sang, thieu khang, thieu quang
hoc thieu » toc thieu, hoc hien
trung cua » truong cua, trung tuan, trung cap
hang cua » mang cua, hang ca, huong cua
cong dan » cong san, cong tan, huong dan
dan than » dan chan, ban than, van than
than cau » toan cau, phan cau, than 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 - hanh ((hang cua) or (trung cua)) thong cong dan than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sang - hanh ((hang cua) OR (trung cua)) thong cong dan than cau.
• Adding a wildcard symbol may retrieve word variants: hoc thieu sang - hanh ((hang cua) or (trung cua)) thong cong dan than cau*.