Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, hieu manh, thien anh
hieu nganh » vien nganh, hiem ngan, hieu manh
hang nong » thang long, han tong
dung cong » dung trong
bai toan » bai tap
toan ban » van ban
ha cong » hoa cong, va cong, ha dong
cong cu » chung cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc ((thieu xanh) or (hieu nganh)) - ha cong cu ((hang nong) or (dung cong)) bai toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((thieu xanh) OR (hieu nganh)) - ha cong cu ((hang nong) OR (dung cong)) bai toan ban.
• Adding a wildcard symbol may retrieve word variants: toc ((thieu xanh) or (hieu nganh)) - ha cong cu ((hang nong) or (dung cong)) bai toan ban*.