Perhaps you should try some spelling variations:
danh tranh » danh thanh, lanh tranh, doanh thanh
sach nganh » sach ngan, sach tranh, cac nganh
thuyet van » thuyet va, thuyet dan, thuyet can
thuat co » thuat do, thuat o
y thuyet » ly thuyet, li thuyet, ly huyet
te sach » toc sach
van hoc » van hoa

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

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