Perhaps you should try some spelling variations:
danh thanh » dinh thanh, dang thanh, nhanh thanh
hoc thieu » toc thieu, hoc hien
doc hieu » toc thieu, hoc hien
qua dung » quang dung, qua song, qua cong
cong tan » cong tac, cong san, cong thanh
tan toan » tan tran, tap toan, van toan
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: ((doc hieu) or (hoc thieu)) manh - danh thanh ((qua dung) OR (su dung)) cong tan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doc hieu) OR (hoc thieu)) manh - danh thanh ((qua dung) OR (su dung)) cong tan toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doc hieu) or (hoc thieu)) manh - danh thanh ((qua dung) OR (su dung)) cong tan toan cau".
• Adding a wildcard symbol may retrieve word variants: ((doc hieu) or (hoc thieu)) manh - danh thanh ((qua dung) OR (su dung)) cong tan toan cau*.