Perhaps you should try some spelling variations:
kxmy thuat » ky thuat, my thuat
sach kxmy » sach kem
kxy thuat » ky thuat, ki thuat, my thuat
thuat do » thuat o
te sach » toc sach
so sach » bo sach, co sach, hoc sach
so sanh » do sanh
vu sach » vu bach, su sach, vu khach
do khi » doi khi, co khi, bo khi

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

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