Perhaps you should try some spelling variations:
thanh tung » thanh cong
thong cong » trong cong, tong cong, phong chong
hieu lang » chieu sang, hieu quang, nhieu tang
tung tuan » trung tuan, hung tuan, quang tuan
hoc hieu » hoc thieu, hoc hien, doc hieu
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 hieu lang - thanh tung tuan ((thong cong) or (thong thong)) dan than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu lang - thanh tung tuan ((thong cong) OR (thong thong)) dan than cau.
• Adding a wildcard symbol may retrieve word variants: hoc hieu lang - thanh tung tuan ((thong cong) or (thong thong)) dan than cau*.