Perhaps you should try some spelling variations:
canh tinh » hanh tinh, manh tinh, canh tranh
sach ngan » sach ngon, sach nha, sach han
thu canh » thuc hanh, thu cong, thu ban
ke thuat » ki thuat, ve thuat, te thuat
toan hoc » toan khoa, van hoc, hoa hoc
tu sach » thu sach, su sach, te sach
ngan ky » nganh ky, nhan ky, ngan hay
thuat o » thuat do
tinh ke » tinh ket, trinh ke, tinh he
o hoc » co hoc, mo hoc, so 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 sach ngan ky thuat o hoc ) or ( thu canh tinh ke thuat toan hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach ngan ky thuat o hoc ) OR ( thu canh tinh ke thuat toan hoc )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach ngan ky thuat o hoc ) or ( thu canh tinh ke thuat toan hoc ))*.