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