Perhaps you should try some spelling variations:
thien chanh » thien thanh, thien chinh, hien hanh
hanh trinh » canh tranh, hanh chinh
trong van » trong cac
trinh va » trinh van, trinh vat, trinh ve
toan cao » toan tap
toan ban » van ban
va dung » van dung, va duong, vat dung

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thien chanh) or (thi thanh)) - hanh trinh va dung trong van ((toan cao) OR (toan ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thien chanh) OR (thi thanh)) - hanh trinh va dung trong van ((toan cao) OR (toan ban)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thien chanh) or (thi thanh)) - hanh trinh va dung trong van ((toan cao) OR (toan ban))".
• Adding a wildcard symbol may retrieve word variants: hoc ((thien chanh) or (thi thanh)) - hanh trinh va dung trong van ((toan cao) OR (toan ban))*.