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
hieu quan » lieu quan, thien quan, lien quan
trung cua » truong cua, trung tuan, trung cap
cua khong » hua khong, cua phuong, cua thuong
thong dan » thong van, tuong dan, thong den
dan phan » doan phan, dan chan, van phan
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: doi ((((hieu quan) or (hieu qua))) or (chieu sang)) - thanh trung cua khong thong dan phan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi ((((hieu quan) OR (hieu qua))) OR (chieu sang)) - thanh trung cua khong thong dan phan cau.
• Adding a wildcard symbol may retrieve word variants: doi ((((hieu quan) or (hieu qua))) or (chieu sang)) - thanh trung cua khong thong dan phan cau*.