Perhaps you should try some spelling variations:
canh trinh » canh tranh, hanh trinh, canh tinh
canh ngon » danh ngon
thuat do » thuat o
trinh ke » trinh ky, trinh he, trinh do
ke thuat » ki thuat, ve thuat, te thuat
toan hoc » toan khoa, van hoc, hoa hoc
tu canh » thu canh, tu chanh, tu can
ngon ky » ngon keo
do hoc » co hoc, do hoa, du hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tu canh ngon ky thuat do hoc ) or ( tu canh trinh ke thuat toan hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu canh ngon ky thuat do hoc ) OR ( tu canh trinh ke thuat toan hoc )).
• Adding a wildcard symbol may retrieve word variants: (( tu canh ngon ky thuat do hoc ) or ( tu canh trinh ke thuat toan hoc ))*.