Perhaps you should try some spelling variations:
bach tuoc » sach duoc, sach nuoc
hanh tai » thanh tai, hang tai, han tai
hanh lai » hanh lam, thanh lap, thanh loi
tuoc va » thuoc va, nuoc va, duoc va
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
ve bach » ve cach, vu bach, vi bach
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
x hoi » o hoi, x ho, 5 hoi

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 ky nang ((x hoi) OR (xa hoi)). hieu ve bach tuoc va ((hanh lai) or (hanh tai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((x hoi) OR (xa hoi)). hieu ve bach tuoc va ((hanh lai) OR (hanh tai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang ((x hoi) OR (xa hoi)). hieu ve bach tuoc va ((hanh lai) or (hanh tai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ((x hoi) OR (xa hoi)). hieu ve bach tuoc va ((hanh lai) or (hanh tai)) cua tre*.