Perhaps you should try some spelling variations:
chiet tach » chieu sach
hanh trinh » canh tranh, hanh chinh
doi chiet » doi chieu, doi chi, doi viet
phong van » phung van, thong van, phong va
trinh va » trinh van, trinh vat, trinh ve
hong van » hoang van, thong van, song van
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: doi chiet tach - hanh trinh va nhung ((hong van) or (phong van)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi chiet tach - hanh trinh va nhung ((hong van) OR (phong van)) toan cao*.