Perhaps you should try some spelling variations:
kxki thuat » khoi thuat
kxy thuat » ky thuat, my thuat, ky thua
toc sach » hoc sach, doc sach, thuoc sach
ki thuat » ky thuat
thuat co » thuat do
sach kxy » sach xa, sach kem, sac ky
sach ki » sach kinh, sach bai, sach kem
tu sach » thu sach, su sach, te sach
thuat o » thuat do
vu sach » vu bach, su sach, vu khach
o 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: (( toc sach ki thuat co khi ) or ((( tu sach kxy thuat o khi ) or ( vu sach kxki thuat o khi ))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( toc sach ki thuat co khi ) OR ((( tu sach kxy thuat o khi ) OR ( vu sach kxki thuat o khi )))).
• Adding a wildcard symbol may retrieve word variants: (( toc sach ki thuat co khi ) or ((( tu sach kxy thuat o khi ) or ( vu sach kxki thuat o khi ))))*.