Perhaps you should try some spelling variations:
thien hach » thien thanh, hien hanh
chiet tach » chieu sach
hanh dung » thanh dung, anh dung, hanh dong
dong cong » duong cong, dang cong, cong cong
dung cong » dung trong
dan chan » dan gian, dan ca, van chat
chan cau » phan cau, can cau, chinh cau

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thien hach) OR (chiet tach)) - hanh dung tai ((dong cong) OR (dung cong)) dan chan cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thien hach) or (chiet tach)) - hanh dung tai ((dong cong) OR (dung cong)) dan chan cau~".
• Adding a wildcard symbol may retrieve word variants: hoc ((thien hach) or (chiet tach)) - hanh dung tai ((dong cong) OR (dung cong)) dan chan cau*.