Perhaps you should try some spelling variations:
thuat cbo » thuat cao, thuat cheo, thuat choi
thuat co » thuat do, thuat o
cbo khi » bo khi, cao khai
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
ky thua » ky thu, kxy thuat, ki thuat
thua o » thuat o, chua o, thua _
o 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: (((( tu cac ky thuat co khi ) OR ( tu cac ky thuat cbo khi ))) or ( su sach ky thua o khi ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((( tu cac ky thuat co khi ) OR ( tu cac ky thuat cbo khi ))) OR ( su sach ky thua o khi )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(((( tu cac ky thuat co khi ) OR ( tu cac ky thuat cbo khi ))) or ( su sach ky thua o khi ))".
• Adding a wildcard symbol may retrieve word variants: (((( tu cac ky thuat co khi ) OR ( tu cac ky thuat cbo khi ))) or ( su sach ky thua o khi ))*.