Perhaps you should try some spelling variations:
kki thuat » ki thuat, khoi thuat, ky thuat
kxy thuat » ky thuat, ki thuat, my thuat
thuat co » thuat do, thuat o
thuat bo » thuat bao, thuat do, thuat o
tu sach » thu sach, tu cach, vu sach
te sach » toc sach
su sach » vu sach
so sach » so sanh, bo sach, co sach
bo thi » bo thit, do thi, bo tai

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) or (te sach)) kki thuat co khi ) or ( ((su sach) OR (so sach)) kxy thuat bo thi ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( ((tu sach) OR (te sach)) kki thuat co khi ) OR ( ((su sach) OR (so sach)) kxy thuat bo thi )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( ((tu sach) or (te sach)) kki thuat co khi ) or ( ((su sach) OR (so sach)) kxy thuat bo thi ))".
• Adding a wildcard symbol may retrieve word variants: (( ((tu sach) or (te sach)) kki thuat co khi ) or ( ((su sach) OR (so sach)) kxy thuat bo thi ))*.