Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
tieu xanh » tieu danh, chieu xanh, dieu hanh
tang luan » dung luan
tang cua » mang cua, hang cua, thong cua
cong tap » cuong tap, cong tac, cong tan
tap toan » tap doan, tap quan, bai toan
toan cau » toan cao, toan ban, toan tap

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "theo tieu xanh - hanh ((tang cua) OR (tang luan)) nhung cong tap toan cau~".
• Adding a wildcard symbol may retrieve word variants: theo tieu xanh - hanh ((tang cua) OR (tang luan)) nhung cong tap toan cau*.