Perhaps you should try some spelling variations:
sach tranh » canh tranh
cac nganh » hoc nganh
thuat hoa » thuat toan, thuyet hoa, thuat do
cao quyet » cach quyet, ra quyet, van quyet
co huyet » co huyen, cay huyet, o huyen
y thuat » ky thuat, my thuat, kxy thuat
tu sach » thu sach, su sach, te sach

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 nganh y thuat hoa hoc ) or ( tu sach tranh ((co huyet) OR (cao quyet)) hoa hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu cac nganh y thuat hoa hoc ) OR ( tu sach tranh ((co huyet) OR (cao quyet)) hoa hoc )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( tu cac nganh y thuat hoa hoc ) or ( tu sach tranh ((co huyet) OR (cao quyet)) hoa hoc ))".
• Adding a wildcard symbol may retrieve word variants: (( tu cac nganh y thuat hoa hoc ) or ( tu sach tranh ((co huyet) OR (cao quyet)) hoa hoc ))*.