Perhaps you should try some spelling variations:
sach nganh » sach ngan, sach tranh, cac nganh
kxy thuat » ky thuat, ky thua
my thuat » ky thuat, va thuat
ki thuat » ky thuat
tu sach » thu sach, su sach, te sach
tu canh » thu canh, tu chanh, tu can
o hoc » co hoc, mo hoc, so hoc
tranh » trinh, thanh, tran
toan » tran

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 nganh ((my thuat) OR (ki thuat)) o hoc ) or ( tu canh tranh kxy thuat toan khoa ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach nganh ((my thuat) OR (ki thuat)) o hoc ) OR ( tu canh tranh kxy thuat toan khoa ))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( tu sach nganh ((my thuat) OR (ki thuat)) o hoc ) or ( tu canh tranh kxy thuat toan khoa ))*".