Perhaps you should try some spelling variations:
trinh quang » tinh quang, trinh quan, tranh quang
hieu lang » chieu sang, hieu quang, nhieu tang
trinh qua » trinh quan, trinh cua, trinh luat
dung cong » dung trong
san toan » van toan, dan toan, manh toan
toan ban » van ban
ho hieu » ho chieu, hoi hieu, nho hieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho hieu lang - hanh ((trinh qua) OR (trinh quang)) ((thong thong) or (dung cong)) san toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho hieu lang - hanh ((trinh qua) OR (trinh quang)) ((thong thong) OR (dung cong)) san toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho hieu lang - hanh ((trinh qua) OR (trinh quang)) ((thong thong) or (dung cong)) san toan ban".
• Adding a wildcard symbol may retrieve word variants: ho hieu lang - hanh ((trinh qua) OR (trinh quang)) ((thong thong) or (dung cong)) san toan ban*.