Perhaps you should try some spelling variations:
tien manh » tien anh, tien thanh, tieng anh
hanh tang » hanh trang, anh tang, hanh mang
tang luan » dung luan
luan hang » luan nang, luan han, luan hung
nong tac » cong tac, nong tan, tuong tac
dong tac » cong tac, dong tai, dong bac
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: theo ((tien manh) or (dieu hanh)) - hanh tang luan hang ((nong tac) OR (dong tac)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((tien manh) OR (dieu hanh)) - hanh tang luan hang ((nong tac) OR (dong tac)) toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((tien manh) or (dieu hanh)) - hanh tang luan hang ((nong tac) OR (dong tac)) toan cau".
• Adding a wildcard symbol may retrieve word variants: theo ((tien manh) or (dieu hanh)) - hanh tang luan hang ((nong tac) OR (dong tac)) toan cau*.