Perhaps you should try some spelling variations:
nam thuoc » nam thuc, nha thuoc, cay thuoc
hieu van » hieu va, thien van, lieu va
tu cach » tu cac
vu sach » vu bach, su sach, vu khach
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
cua tre » cua te, cuu tre, cua triet
anh va » hanh va
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: ((tu cach) or (vu sach)) ky lang xa hoi. hieu van ((nam thuoc) OR (nam thu)) tuan anh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (vu sach)) ky lang xa hoi. hieu van ((nam thuoc) OR (nam thu)) tuan anh va cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu cach) or (vu sach)) ky lang xa hoi. hieu van ((nam thuoc) OR (nam thu)) tuan anh va cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (vu sach)) ky lang xa hoi. hieu van ((nam thuoc) OR (nam thu)) tuan anh va cua tre*.