Perhaps you should try some spelling variations:
sach ngan » sach ngon, sach nha, sach han
thuat do » thuat o
toan hoc » toan khoa, van hoc, hoa hoc
tu sach » thu sach, su sach, te sach
y thuat » ky thuat, my thuat, kxy thuat
so sach » so sanh, bo sach, co sach
ngan y » nganh y, nhan y, nganh ky
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 sach ngan y thuat do hoa ) or ( so sach ((hanh ky) or (hanh kem)) thuat toan hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach ngan y thuat do hoa ) OR ( so sach ((hanh ky) OR (hanh kem)) thuat toan hoc )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach ngan y thuat do hoa ) or ( so sach ((hanh ky) or (hanh kem)) thuat toan hoc ))*.