Perhaps you should try some spelling variations:
lang trong » dung trong, cong trong, dong trong
hieu lang » chieu sang, hieu quang, nhieu tang
trong dan » trong dang, trong san, trong tan
toc hieu » toc thieu, doc hieu, hoc thieu
dan dung » van dung, tin dung, ap dung
dong dat » dong vat, dong ha, dong tai
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 - lang trong dan dung ((dong dat) OR (dung dat)) phan tu~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc hieu lang - lang trong dan dung ((dong dat) OR (dung dat)) phan tu".
• Adding a wildcard symbol may retrieve word variants: toc hieu lang - lang trong dan dung ((dong dat) OR (dung dat)) phan tu*.