Perhaps you should try some spelling variations:
thuoc phap » thuoc phai, thuc pham, hoc phap
phap sinh » phau sinh, phai sinh, phap tinh
cay thuoc » cua thuoc, nam thuoc, va thuoc
toc sach » hoc sach, doc sach, thuoc sach
sach ky » sac ky, sach y, sach ty
mang xa » lang xa, mang may, dang xay
va cua » va chua, via cua, ma cua
ca cua » co cua
va cay » va cac, va cao, va cai

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky ((mang xa) or (nang x)) hoi. lieu va cay thuoc phap sinh ((va cua) OR (ca cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky ((mang xa) OR (nang x)) hoi. lieu va cay thuoc phap sinh ((va cua) OR (ca cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky ((mang xa) or (nang x)) hoi. lieu va cay thuoc phap sinh ((va cua) OR (ca cua)) tre".
• Adding a wildcard symbol may retrieve word variants: toc sach ky ((mang xa) or (nang x)) hoi. lieu va cay thuoc phap sinh ((va cua) OR (ca cua)) tre*.