Perhaps you should try some spelling variations:
thien danh » thien anh, thien thanh, thien chanh
thien dang » thien bang, thien nang, thien cong
hanh trinh » canh tranh, hanh chinh
tong cong » cong cong, dung cong, dang cong
trinh va » trinh van, trinh vat, trinh ve
tac toan » tap toan, tam toan, hach toan
toan cao » toan ban, toan tap

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

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