Perhaps you should try some spelling variations:
nam thuoc » nam thuc, nam thu, nha thuoc
thuoc dat » thuoc bat, thuoc dac, thuoc dang
hieu van » hieu va, thien van, lieu va
thanh vi » thanh va, thanh ve, nhanh vi
tu sach » thu sach, su sach, te sach
so sach » so sanh, bo sach, co sach
nang xa » nang x, lang xa, nang ma
cuu tre » cua tre, cau tren, cau treo

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) or (so sach)) ky nang xa hoi. hieu van nam thuoc dat ((thanh vi) OR (hanh vi)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (so sach)) ky nang xa hoi. hieu van nam thuoc dat ((thanh vi) OR (hanh vi)) cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (so sach)) ky nang xa hoi. hieu van nam thuoc dat ((thanh vi) OR (hanh vi)) cuu tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (so sach)) ky nang xa hoi. hieu van nam thuoc dat ((thanh vi) OR (hanh vi)) cuu tre*.