Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
thanh luc » thanh luu, than luc, nhan luc
hanh vai » hanh va, hanh tai, hanh van
hieu van » hieu va, thien van, lieu va
luc van » luoc van, luu van, duc van
tu sach » thu sach, su sach, te sach
cua tre » cua te, cuu tre, cua triet
sach v » sach va, sach y, sach 2
ma hoi » mai hoi, ma hoa, me hoi
v nang » va nang, vu nang, van nang

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