Perhaps you should try some spelling variations:
thuoc toan » thuoc tan, thuoc thanh, thuat toan
phau thong » phap thong, phan thong, phan thuong
khau thong » khau thuong, khap thong, khau tong
cay thuoc » cua thuoc, nam thuoc, va thuoc
sach cay » sach cap, sach hay, sach nay
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 sach cay thuoc toan khoa ((phau thong) OR (khau thong))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach cay thuoc toan khoa ((phau thong) OR (khau thong))".
• Adding a wildcard symbol may retrieve word variants: tu sach cay thuoc toan khoa ((phau thong) OR (khau thong))*.