Perhaps you should try some spelling variations:
kki thuat » ki thuat, khoi thuat, ky thuat
sach kki » sach bai, sach kem, sach doi
thuat co » thuat do, thuat o
thuat bo » thuat bao, thuat do, thuat o
tu sach » thu sach, te sach, tu cach
su sach » so sach, vu sach
y thuat » ky thuat, my thuat, kxy thuat
bo khi » bo chi, bo thi

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 kki thuat co khi ) or ( su sach y thuat bo khi ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach kki thuat co khi ) OR ( su sach y thuat bo khi )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach kki thuat co khi ) or ( su sach y thuat bo khi ))*.