Perhaps you should try some spelling variations:
thiet danh » thien danh, thien anh, thien dang
hanh trinh » canh tranh, hanh chinh
cong ngang » cong nhan, cong quang, cong lang
hoc thiet » hoc thieu, hoc thuyet, hoc hien
trinh hon » trinh hoan, trinh han, trinh hoa
hon nhung » hoa nhung, hoc nhung, thong nhung
cong vang » cong lang, cong quang, cong san
than cau » toan cau, phan cau, thanh chau
than cap » khan cap, thanh lap, thanh cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thiet danh - hanh trinh hon nhung ((cong vang) or (cong ngang)) ((than cau) OR (than cap))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thiet danh - hanh trinh hon nhung ((cong vang) OR (cong ngang)) ((than cau) OR (than cap)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thiet danh - hanh trinh hon nhung ((cong vang) or (cong ngang)) ((than cau) OR (than cap))".
• Adding a wildcard symbol may retrieve word variants: hoc thiet danh - hanh trinh hon nhung ((cong vang) or (cong ngang)) ((than cau) OR (than cap))*.