Perhaps you should try some spelling variations:
nhung cong » dung cong, hang cong, nhung don
canh trinh » canh tranh, hanh trinh, canh tinh
thong cong » trong cong, tong cong, thong thong
trinh vat » trinh van, trinh luat, sinh vat
chi xanh » chi anh, chi danh, chi hanh
phan cau » phan dau, phan cac, phan tu
hang dau » hang va, hang tai
doi chi » doi khi

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi chi xanh - canh trinh vat ((nhung cong) OR (thong cong)) dan ((phan cau) or (hang dau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi chi xanh - canh trinh vat ((nhung cong) OR (thong cong)) dan ((phan cau) OR (hang dau)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi chi xanh - canh trinh vat ((nhung cong) OR (thong cong)) dan ((phan cau) or (hang dau))".
• Adding a wildcard symbol may retrieve word variants: doi chi xanh - canh trinh vat ((nhung cong) OR (thong cong)) dan ((phan cau) or (hang dau))*.