Perhaps you should try some spelling variations:
thang duong » thanh duong, thong duong, tang duong
dung thang » hung thang, cung thang, dung thuong
dong thanh » truong thanh
phan hieu » van hieu, phan kien, gian hieu
hieu lang » chieu sang, hieu quang, nhieu tang
duong van » duong va, luong va, dang van
ban tap » bai tap, han tap, ban tai

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

• Performing a fuzzy search may retrieve terms with similar spellings: phan hieu lang - thanh ((dung thang) or (dong thanh)) thang duong van ban tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: phan hieu lang - thanh ((dung thang) OR (dong thanh)) thang duong van ban tap.
• Adding a wildcard symbol may retrieve word variants: phan hieu lang - thanh ((dung thang) or (dong thanh)) thang duong van ban tap*.