Perhaps you should try some spelling variations:
kxy thuat » ky thuat, ki thuat, my thuat
hoach kxy » hoach xay
thuat co » thuat o
thuat do » thuat o
tu sach » thu sach, te sach, tu cach
y thuat » ky thuat, my thuat, ki thuat
su sach » so sach, vu sach
do khi » doi khi, do thi, 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 y thuat co khi ) or ( thu hoach kxy thuat co khi ))) or ( su sach y thuat do khi ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((( tu sach y thuat co khi ) OR ( thu hoach kxy thuat co khi ))) OR ( su sach y thuat do khi )).
• Adding a wildcard symbol may retrieve word variants: (((( tu sach y thuat co khi ) or ( thu hoach kxy thuat co khi ))) or ( su sach y thuat do khi ))*.