Perhaps you should try some spelling variations:
chiet tach » chieu sach
thien hach » thien thanh, hien hanh
quang dong » quang dung, quan dong, quang cuong
dong huong » dong thuong, dong duong, cong huong
hanh tran » hanh trang, thanh tran, hanh tram
dan toan » van toan, dan than, manh toan
toan cau » 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: hoc ((chiet tach) or (thien hach)) - hanh tran quang dong huong dan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chiet tach) OR (thien hach)) - hanh tran quang dong huong dan toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((chiet tach) or (thien hach)) - hanh tran quang dong huong dan toan cau*.