Perhaps you should try some spelling variations:
theo chieu » theo tieu, ho chieu, theo chu
chieu sach » chinh sach, chiet tach, chieu sang
canh trinh » canh tranh, hanh trinh, canh tinh
trinh van » trinh han, trinh quan, trinh toan
nang cong » nang song, dang cong, bang cong
van nang » van quang, van ban, van dong
dan toan » van toan, manh toan, xuan toan
dan than » dan chan, ban than, van than

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "theo chieu sach - canh trinh van nang cong ((dan toan) OR (dan than)) ban~".
• Adding a wildcard symbol may retrieve word variants: theo chieu sach - canh trinh van nang cong ((dan toan) OR (dan than)) ban*.