Perhaps you should try some spelling variations:
sach tranh » canh tranh
sanh nganh » anh ngan, dang nganh, sach ngan
thuat hoa » thuat toan, thuyet hoa, thuat do
sach danh » sach dao, sach dung, sach kinh
va thuat » ky thuat, ki thuat, va thuc
so sanh » do sanh
y thuat » ky thuat, my thuat, kxy thuat

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

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