Perhaps you should try some spelling variations:
nha thuoc » nha nuoc, nhan thuc, nha hoc
hieu van » hieu va, thien van, lieu va
nam duoc » nam thuoc, da duoc, dat duoc
te sach » toc sach
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
va danh » va dinh, va dan, va hanh
danh va » doanh va, hanh va, anh va
cua tre » cua te, cuu tre, cua triet
va cua » va chua, via cua, ca cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky lang xa hoi. hieu van ((nam duoc) or (nha thuoc)) va danh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky lang xa hoi. hieu van ((nam duoc) OR (nha thuoc)) va danh va cua tre.
• Adding a wildcard symbol may retrieve word variants: te sach ky lang xa hoi. hieu van ((nam duoc) or (nha thuoc)) va danh va cua tre*.