Perhaps you should try some spelling variations:
giau cua » gian cua, gia cua, dieu cua
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
qua cac » cua cac
cac luc » cau luc, coc luc, cac nuoc
via cua » gia cua, gian cua, rija cua
y nang » ky nang, ly nang, v nang
va dan » ca dan, va dau, va dap
va dao » ca dao

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 y nang xa hoi. hieu qua cac luc ((va dan) OR (va dao)) ((via cua) or (giau cua)) viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang xa hoi. hieu qua cac luc ((va dan) OR (va dao)) ((via cua) OR (giau cua)) viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang xa hoi. hieu qua cac luc ((va dan) OR (va dao)) ((via cua) or (giau cua)) viet".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang xa hoi. hieu qua cac luc ((va dan) OR (va dao)) ((via cua) or (giau cua)) viet*.