Perhaps you should try some spelling variations:
tieu hieu » tieu bieu, thien hieu, tieu khien
hieu cac » hieu luc, hieu va, hieu van
toc sach » hoc sach, doc sach, thuoc sach
nang xa » nang x, lang xa, nang ma
sach ky » sac ky, sach y, sach ty
via cua » gia cua, gian cua, giau cua
xac va » tac va, ac va, bac va
tuc va » thuc va, truc va, tuc xa
va cua » va chua, ca cua, ma cua

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 xa hoi. tieu hieu cac ((xac va) or (tuc va)) hanh ((va cua) OR (via cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang xa hoi. tieu hieu cac ((xac va) OR (tuc va)) hanh ((va cua) OR (via cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky nang xa hoi. tieu hieu cac ((xac va) or (tuc va)) hanh ((va cua) OR (via cua)) triet".
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang xa hoi. tieu hieu cac ((xac va) or (tuc va)) hanh ((va cua) OR (via cua)) triet*.