Perhaps you should try some spelling variations:
hanh vai » hanh va, hanh tai, hanh van
tu sach » thu sach, su sach, te sach
cam luc » cam xuc, cau luc
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
ky sang » ky nang, ky dang, ky tang
ma hoi » mai hoi, ma hoa, me hoi
luc va » duc va, tuc va, loc va
ve cam » ve cham, ve cac, va cam

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 sang ((ma hoi) or (xa hoi)). hieu ve cam luc va ((hanh vai) or (hanh vi)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky sang ((ma hoi) OR (xa hoi)). hieu ve cam luc va ((hanh vai) OR (hanh vi)) cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky sang ((ma hoi) or (xa hoi)). hieu ve cam luc va ((hanh vai) or (hanh vi)) cua tre*.