Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh tai, hanh van
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
hanh va » hang va, hanh vi
duc van » duc va, duc tan, duc manh
cua tre » cua te, cuu tre, cua triet
duc ban » duc tan, dua ban, duc man
van cam » van nam, van lam, van cau
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang

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