Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
qua cac » cua cac
y nang » ky nang, ly nang, v nang
luc va » duc va, loc va
tuc va » thuc va, truc va, tuc xa
dan va » doan va, dan ca, han va

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) OR (tuc va)) ((dan va) or (ban va)) 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) OR (tuc va)) ((dan va) OR (ban va)) 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) OR (tuc va)) ((dan va) or (ban va)) cua viet".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang xa hoi. hieu qua cac ((luc va) OR (tuc va)) ((dan va) or (ban va)) cua viet*.