Perhaps you should try some spelling variations:
thuyet vah » thuyet mach, thuyet hach, thuyet canh
hanh trung » thanh trung, hanh trang, manh trung
trung cua » truong cua, trung tuan, trung cap
cua trong » cua truong, cua trung, qua trong
cong dan » cong san, huong dan, cong dong
cong tan » cong tac, cong san, cong thanh
toan cau » 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: hoc ((thuyet vah) or (thuyet va)) - hanh trung cua trong ((cong dan) OR (cong tan)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thuyet vah) OR (thuyet va)) - hanh trung cua trong ((cong dan) OR (cong tan)) toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thuyet vah) or (thuyet va)) - hanh trung cua trong ((cong dan) OR (cong tan)) toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((thuyet vah) or (thuyet va)) - hanh trung cua trong ((cong dan) OR (cong tan)) toan cau*.