Perhaps you should try some spelling variations:
thiet tach » chiet tach, thien hach, thuat tach
hanh trang » thanh trung, hanh trinh, minh trang
hoc thiet » hoc thieu, hoc thuyet, hoc hien
dung cong » dung trong
van dung » van dong, xay dung, tin dung
cong tan » cong tac, cong san, cong thanh
than cau » toan cau, phan cau, than cap
phan cac » nhan cach, phan dau, phan lap

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 thiet tach - ((hanh trang) OR (canh tranh)) van dung cong tan ((than cau) OR (phan cac))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thiet tach - ((hanh trang) OR (canh tranh)) van dung cong tan ((than cau) or (phan cac))~".
• Adding a wildcard symbol may retrieve word variants: hoc thiet tach - ((hanh trang) OR (canh tranh)) van dung cong tan ((than cau) or (phan cac))*.