Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
va triet » va thiet, va trien, ve triet
hieu ve » hieu van
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
dinh vu » dich vu, dinh ve, dinh cu
xuc va » duc va, tuc va, xac va
luc va » duc va, tuc va, loc va
x hoi » xa hoi, o hoi, x ho
vu va » vu van, tu va, su va

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky nang x hoi. ((hieu ve) or (hieu va)) cam ((xuc va) or (luc va)) dinh vu va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang x hoi. ((hieu ve) OR (hieu va)) cam ((xuc va) OR (luc va)) dinh vu va triet.
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang x hoi. ((hieu ve) or (hieu va)) cam ((xuc va) or (luc va)) dinh vu va triet*.