Perhaps you should try some spelling variations:
hoang van » hang va
ban hanh » ban hang
cao xuc » cam xuc, cao duc, cao suc
lai cua » dai cua, hai cua, lai chau
vai cua » dai cua, hai cua, bai cua
xuc ban » duc ban, cuc ban, quoc ban
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
sang ma » tang ma, nang ma, sang tao
hieu va » lieu va, hieu qua
va cao » va cac, va co, va dao

You may be able to get more results by adjusting your search query.

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