Perhaps you should try some spelling variations:
kinh thuat » ki thuat, dich thuat, ninh thuan
kxy thuat » ki thuat, my thuat, ky thua
thuat bo » thuat bao, thuat do, thuat o
tu sach » thu sach, te sach, tu cach
vu sach » vu bach, vu khach
su sach » so sach
bo khi » co khi, bo chi, bo thi
o khi » co 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 kinh thuat bo khi ) or ( ((vu sach) OR (su sach)) ((kxy thuat) or (ky thuat)) o khi ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach kinh thuat bo khi ) OR ( ((vu sach) OR (su sach)) ((kxy thuat) OR (ky thuat)) o khi ))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( tu sach kinh thuat bo khi ) or ( ((vu sach) OR (su sach)) ((kxy thuat) or (ky thuat)) o khi ))*".