Perhaps you should try some spelling variations:
sang lap » sang tao, sang ma, sang tai
van dinh » van minh, van dich, va dinh
hieu van » thien van, lieu va, hieu ve
bo sach » co sach, hoc sach
cac luc » cau luc, coc luc, cac nuoc
va danh » va dinh, va dan, va hanh
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
lap hai » lap tai, lap lai, lap hoat
ky sang » ky nang, ky dang, ky tang
vi cua » vai cua, di cua
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: bo sach ky sang lap hai. ((hieu van) OR (hieu va)) cac luc ((va danh) or (van dinh)) vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: bo sach ky sang lap hai. ((hieu van) OR (hieu va)) cac luc ((va danh) OR (van dinh)) vi cua te*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "bo sach ky sang lap hai. ((hieu van) OR (hieu va)) cac luc ((va danh) or (van dinh)) vi cua te*".