Perhaps you should try some spelling variations:
kki thuat » ki thuat, khoi thuat, ky thuat
kxy thuat » ky thuat, ki thuat, my thuat
khac kki » khac di, khac dai, khac thi
ty thuat » ky thuat, my thuat, te thuat
sach kxy » sach xa, sach kem, sac ky
vu khac » vu kham, vu khanh, bui khac
vu sach » vu bach, vu khach
sach ty » sach y, sach tu, sach thu
su sach » so sach
do khi » doi khi, do thi, co khi
o khi » 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: (( vu khac kki thuat do khi ) or ((( vu sach ty thuat o khi ) or ( su sach kxy thuat o khi ))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( vu khac kki thuat do khi ) OR ((( vu sach ty thuat o khi ) OR ( su sach kxy thuat o khi )))).
• Adding a wildcard symbol may retrieve word variants: (( vu khac kki thuat do khi ) or ((( vu sach ty thuat o khi ) or ( su sach kxy thuat o khi ))))*.