Perhaps you should try some spelling variations:
chiet tach » chieu sach
hanh trinh » canh tranh, hanh chinh
ho chiet » ho chieu, ho thiet, hoc thiet
trinh ve » trinh he, trinh va, trinh vi
cong van » cong vang, song van, cong tan
cong san » cong tac
ve dung » ve duong, ve rung, va dung
tai tap » bai tap, tai tao, hai tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho chiet tach - hanh trinh ve dung ((cong van) OR (cong san)) tai tap~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho chiet tach - hanh trinh ve dung ((cong van) OR (cong san)) tai tap".
• Adding a wildcard symbol may retrieve word variants: ho chiet tach - hanh trinh ve dung ((cong van) OR (cong san)) tai tap*.