Perhaps you should try some spelling variations:
thuat doi » thuat di, thuat doc, thuat moi
kxy thuat » ky thuat, my thuat, ky thua
thuat don » thuat dong, thuat dan, thuat doc
ki thuat » ky thuat
thuat do » thuat o
sach kxy » sach xa, sach kem, sac ky
thu sach » thuat sach, thuoc sach, thu hoach
tu sach » su sach, tu cach, vu sach
sach ki » sach kinh, sach bai, sach kem
te sach » toc sach
y thuat » ky thuat, my thuat, va thuat
don khi » dong khi, duong khi, cong khi
do khi » do thi, 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: (( tu sach ki thuat do khi ) or ((( te sach kxy thuat doi khi ) or ( thu sach y thuat don khi ))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach ki thuat do khi ) OR ((( te sach kxy thuat doi khi ) OR ( thu sach y thuat don khi )))).
• Adding a wildcard symbol may retrieve word variants: (( tu sach ki thuat do khi ) or ((( te sach kxy thuat doi khi ) or ( thu sach y thuat don khi ))))*.