Perhaps you should try some spelling variations:
hoc thieu » toc thieu, hoc hien
hanh tang » hanh trang, anh tang, hanh mang
doc hieu » toc thieu, hoc hien
cong dan » cong san, huong dan, cong dong
cong tan » cong tac, cong san, cong thanh
toan cao » toan ban, toan tap
tang va » trang va, tang van, thang va
va hang » van hang, va nang, va lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc thieu) or (doc hieu)) manh - hanh tang va hang ((cong dan) OR (cong tan)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc thieu) OR (doc hieu)) manh - hanh tang va hang ((cong dan) OR (cong tan)) toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc thieu) or (doc hieu)) manh - hanh tang va hang ((cong dan) OR (cong tan)) toan cao".
• Adding a wildcard symbol may retrieve word variants: ((hoc thieu) or (doc hieu)) manh - hanh tang va hang ((cong dan) OR (cong tan)) toan cao*.