Perhaps you should try some spelling variations:
sach nganh » sach ngan, sach tranh, cac nganh
mac thuat » cac thuat, my thuat, va thuat
thuat hoa » thuat toan, thuyet hoa, thuat do
ma thuat » my thuat, va thuat, mi thuat
nganh ky » nganh y, nganh xay, hanh ky
su sach » so sach, vu sach
van hoc » van hoa
bo sach » co sach, hoc sach

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