Perhaps you should try some spelling variations:
thanh phan » thanh pho, thanh san, thanh toan
hieu lang » chieu sang, hieu quang, nhieu tang
toc hieu » toc thieu, doc hieu, hoc thieu
phan dat » phan dau, phan dai, phan day
dat dung » dan dung, vat dung, da dung
vung dat » vung va
dung dat » dung va, dung tai

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

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