Perhaps you should try some spelling variations:
canh thanh » canh tranh, danh thanh, anh thanh
cac nganh » hoc nganh
thanh kim » thanh liem, thanh kinh, khanh kiem
kim thuat » kiem thuat, ki thuat, ky thuat
nganh va » nganh vat, nganh ma, nhanh va
va thuat » ky thuat, ki thuat, va thuc
toan hoc » toan khoa, van hoc, hoa hoc
tu canh » thu canh, tu chanh, tu can
do hoc » co hoc, du hoc, mo hoc
do hoa » dong hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tu cac nganh va thuat ((do hoc) OR (do hoa)) ) or ( tu canh thanh kim thuat toan hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu cac nganh va thuat ((do hoc) OR (do hoa)) ) OR ( tu canh thanh kim thuat toan hoc ))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( tu cac nganh va thuat ((do hoc) OR (do hoa)) ) or ( tu canh thanh kim thuat toan hoc ))*".