Perhaps you should try some spelling variations:
nang mai » nang ma, nang tai, lang mai
mai khoi » mai khoa, tai khoa, cac khoi
tu sach » thu sach, su sach, te sach
xuc ban » duc ban, cuc ban, quoc ban
banh vi » ban vi, benh vi, banh chi
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
hieu ve » hieu van
cua tre » cua te, cuu tre, cua triet

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 mai khoi. ((hieu ve) or (hieu va)) cam xuc ban ((banh vi) or (hanh vi)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang mai khoi. ((hieu ve) OR (hieu va)) cam xuc ban ((banh vi) OR (hanh vi)) cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang mai khoi. ((hieu ve) or (hieu va)) cam xuc ban ((banh vi) or (hanh vi)) cua tre*.