Perhaps you should try some spelling variations:
chiet tach » chieu sach
hanh trinh » hanh chinh
doi chiet » doi chieu, doi chi, doi viet
nang cong » nang song, bang cong, hang cong
dang cong » dung cong
van tuan » van quan, van ban, anh tuan
tuan cao » toan cao, juan cao, quang cao

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) or (canh tranh)) va ((nang cong) OR (dang cong)) van tuan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi chiet tach - ((hanh trinh) OR (canh tranh)) va ((nang cong) OR (dang cong)) van tuan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi chiet tach - ((hanh trinh) or (canh tranh)) va ((nang cong) OR (dang cong)) van tuan cao".
• Adding a wildcard symbol may retrieve word variants: doi chiet tach - ((hanh trinh) or (canh tranh)) va ((nang cong) OR (dang cong)) van tuan cao*.