Perhaps you should try some spelling variations:
thanh dong » thanh duong, thanh cong, hanh dong
hoc thieu » toc thieu, hoc hien
dung cong » dung trong
ho chieu » theo chieu, doi chieu, mot chieu
dong hoc » dong co, dong luc
hoc dung » hoc ung, hoc dan, tac dung
van tan » van tuan, van tai, van thanh

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((ho chieu) or (hoc thieu)) sach - thanh dong hoc dung cong ((van tan) or (van ban)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (hoc thieu)) sach - thanh dong hoc dung cong ((van tan) OR (van ban)) cao.
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) or (hoc thieu)) sach - thanh dong hoc dung cong ((van tan) or (van ban)) cao*.