Perhaps you should try some spelling variations:
duong vanh » duong van, duong manh, duong xanh
thuc xanh » thuc hanh, thuc thanh, thuy anh
tranh cua » doanh cua, manh cua
cua tuong » cua truong, cua thuong, cua huong
duong anh » duong manh, duong xanh, dong anh
thuc dan » thuc hanh, hoc dan, thuc vat
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: choi ((thuc xanh) OR (thuc dan)) - canh tranh cua tuong ((duong anh) or (duong vanh)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: choi ((thuc xanh) OR (thuc dan)) - canh tranh cua tuong ((duong anh) OR (duong vanh)) toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "choi ((thuc xanh) OR (thuc dan)) - canh tranh cua tuong ((duong anh) or (duong vanh)) toan cau".
• Adding a wildcard symbol may retrieve word variants: choi ((thuc xanh) OR (thuc dan)) - canh tranh cua tuong ((duong anh) or (duong vanh)) toan cau*.