Perhaps you should try some spelling variations:
kxky thuat » kxy thuat
sach tranh » canh tranh
sach hanh » sach danh, sach han, sac hanh
duoc hoc » quoc hoi
toan hoc » toan khoa, van hoc, hoa hoc
su sach » so sach, vu sach
hanh ky » hanh kem
du hoc » tu hoc

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( su sach hanh ky thuat ((du hoc) OR (duoc hoc)) ) or ( su sach tranh kxky thuat toan hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( su sach hanh ky thuat ((du hoc) OR (duoc hoc)) ) OR ( su sach tranh kxky thuat toan hoc )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( su sach hanh ky thuat ((du hoc) OR (duoc hoc)) ) or ( su sach tranh kxky thuat toan hoc ))".
• Adding a wildcard symbol may retrieve word variants: (( su sach hanh ky thuat ((du hoc) OR (duoc hoc)) ) or ( su sach tranh kxky thuat toan hoc ))*.