Perhaps you should try some spelling variations:
dang xay » dang van, van xay
cua viet » ca viet, hoa viet, cua vat
tu sach » thu sach, su sach, te sach
lang xa » lang ha, lang van
qua cac » cua cac
cac loc » cac lop, cac toc, cac hoc
loc va » hoc va, luc va
va dan » ca dan, va dao, va dau
dan va » doan va, dan ca, ban va
va cua » va chua, via cua, ca cua

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 ((lang xa) or (dang xay)) hoi. hieu qua cac loc va dan va cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((lang xa) OR (dang xay)) hoi. hieu qua cac loc va dan va cua viet.
• Adding a wildcard symbol may retrieve word variants: tu sach y ((lang xa) or (dang xay)) hoi. hieu qua cac loc va dan va cua viet*.