Perhaps you should try some spelling variations:
thuat hoc » thuat hoa, thuat thuc, thuat phuc
thuat doc » thuat duoc, thuat doi, thuat don
hoc khoi » hoc khoa, hoc hoa, hoc noi
thuat do » thuat o
so sach » so sanh, bo sach, co sach
sach ky » sac ky, sach ty, sach kem
doc khi » doi khi, hoc khi, dong khi
te sach » toc sach
y thuat » my thuat, kxy thuat, ki thuat

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((( so sach ky thuat doc khi ) OR ( so sach ky thuat hoc khoi ))) or ( te sach y thuat do thi ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((( so sach ky thuat doc khi ) OR ( so sach ky thuat hoc khoi ))) OR ( te sach y thuat do thi )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(((( so sach ky thuat doc khi ) OR ( so sach ky thuat hoc khoi ))) or ( te sach y thuat do thi ))".
• Adding a wildcard symbol may retrieve word variants: (((( so sach ky thuat doc khi ) OR ( so sach ky thuat hoc khoi ))) or ( te sach y thuat do thi ))*.