Perhaps you should try some spelling variations:
kxy thuat » ky thuat, ki thuat, my thuat
sach kxy » sach xa, sach kem, sach y
thuat do » thuat o
thuat di » thuat dia, thuat doi, thuat de
su sach » so sach, vu sach
do khi » doi khi, do thi, co khi
sac ky » cac ky, sai ky
di khi » doi khi, li khi, di chi

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( su sach kxy thuat do khi ) or ( su ((sach kxy) or (sac ky)) thuat di khi ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( su sach kxy thuat do khi ) OR ( su ((sach kxy) OR (sac ky)) thuat di khi )).
• Adding a wildcard symbol may retrieve word variants: (( su sach kxy thuat do khi ) or ( su ((sach kxy) or (sac ky)) thuat di khi ))*.