Perhaps you should try some spelling variations:
thong quang » thong quan, thong qua, thong dung
luong quang » luong quan, dung quang
trung huong » truong huong, trung uong, trung duong
theo chieu » theo tieu, ho chieu, theo chu
chieu sach » chinh sach, chiet tach, chieu sang
dan toan » van toan, dan than, manh toan
toan cao » toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo chieu sach - anh ((thong quang) or (luong quang)) trung huong dan toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo chieu sach - anh ((thong quang) OR (luong quang)) trung huong dan toan cao.
• Adding a wildcard symbol may retrieve word variants: theo chieu sach - anh ((thong quang) or (luong quang)) trung huong dan toan cao*.