Perhaps you should try some spelling variations:
thanh trung » thanh tung
khong thong » thong thong, khong trong, thong thuong
chieu sang » chieu sach, chieu xanh, hieu lang
thong doan » thong dan, trong doanh, thong hoang
trung cua » truong cua, trung tuan, trung cap
cua khong » hua khong, cua phuong, cua thuong
phan cau » phan cac, phan tu, phan lap
phan dau » phan tu, hang dau
hieu va » lieu va, hieu qua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: doi ((hieu va) or (chieu sang)) - thanh trung cua khong thong doan ((phan cau) OR (phan dau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi ((hieu va) OR (chieu sang)) - thanh trung cua khong thong doan ((phan cau) OR (phan dau)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi ((hieu va) or (chieu sang)) - thanh trung cua khong thong doan ((phan cau) OR (phan dau))".
• Adding a wildcard symbol may retrieve word variants: doi ((hieu va) or (chieu sang)) - thanh trung cua khong thong doan ((phan cau) OR (phan dau))*.