Perhaps you should try some spelling variations:
khanh vi » khanh v, nhanh vi, khang vi
thu sach » thuat sach, thuoc sach, thu hoach
tu sach » su sach, te sach, tu cach
xuc van » duc van, luc van, vuc van
cao xuc » cam xuc, cao duc, cao suc
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
ma hoi » mai hoi, xa hoi, ma hoa
va cao » va cac, va co, va dao

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