Perhaps you should try some spelling variations:
chiet tach » chieu sach
hanh trinh » canh tranh
quan thong » quang thong, quan trong, xuan thong
thong cong » trong cong, tong cong, thong thong
hoc chiet » hoc thiet, hoc nhiet, hoc hien
sang than » cang thang, dang thanh, sang tao
san than » san thanh, ban than, van than

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc chiet tach - ((hanh trinh) OR (hanh chinh)) quan thong cong ((san than) OR (sang than)) ban~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc chiet tach - ((hanh trinh) or (hanh chinh)) quan thong cong ((san than) OR (sang than)) ban~".
• Adding a wildcard symbol may retrieve word variants: hoc chiet tach - ((hanh trinh) or (hanh chinh)) quan thong cong ((san than) OR (sang than)) ban*.