Perhaps you should try some spelling variations:
van khanh » van thanh, van hanh, van anh
khanh ve » hanh ve, thanh ve, khanh v
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
hieu va » hieu qua
xuc van » duc van, luc van, vuc van
ve cau » ke cau, va cau, ve cac
x hoi » xa hoi, x ho, 5 hoi
o hoi » co hoi, o hoc, o hai

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 ((x hoi) OR (o hoi)). ((hieu va) or (lieu va)) cam xuc van khanh ve cau thi~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((x hoi) OR (o hoi)). ((hieu va) OR (lieu va)) cam xuc van khanh ve cau thi.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang ((x hoi) OR (o hoi)). ((hieu va) or (lieu va)) cam xuc van khanh ve cau thi".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ((x hoi) OR (o hoi)). ((hieu va) or (lieu va)) cam xuc van khanh ve cau thi*.