Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, hieu manh, thien anh
hanh trinh » canh tranh, hanh chinh
trinh vat » trinh van, trinh luat, sinh vat
dung cong » dung trong
hang cong » dang cong, hang nong, bang cong
van than » van thanh, van thang, van tuan
than tap » toan tap, han tap, phan tap

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 - hanh trinh vat ((dung cong) or (hang cong)) van than tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc thieu xanh - hanh trinh vat ((dung cong) OR (hang cong)) van than tap.
• Adding a wildcard symbol may retrieve word variants: toc thieu xanh - hanh trinh vat ((dung cong) or (hang cong)) van than tap*.