Perhaps you should try some spelling variations:
sach tranh » canh tranh
sach nganh » sach ngan, cac nganh, sach danh
xay thuyet » thay thuyet, ly thuyet, bai thuyet
nganh xay » nganh mac, nganh y, nganh ma
tranh ky » trinh ky, thanh ky, hanh ky
te sach » toc sach
do hoc » co hoc, do hoa, mo hoc
du hoc » tu hoc, duoc hoc
va hoc » van hoc

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

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