Perhaps you should try some spelling variations:
may trinh » may tinh, lap trinh, quy trinh
trinh vi » trinh va, trinh ve, trinh viet
cua viet » hoa viet, cua vat, cua dieu
dang xay » dang van, van xay
ca viet » va viet, co viet, hoa viet
lang xa » lang ha, lang van
hieu ve » hieu va, hieu van
cac loc » cac lop, cac toc, cac hoc
loc may » hoc may, loc mau, loai may
so sac » so sach, so dac
sac ky » cac ky, sai ky
ve cac » va cac, vien cac

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

• If you are trying to use Boolean operators, they must be ALL CAPS: so sac ky ((lang xa) OR (dang xay)) hoi. hieu ve cac loc may trinh vi ((cua viet) OR (ca viet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sac ky ((lang xa) OR (dang xay)) hoi. hieu ve cac loc may trinh vi ((cua viet) or (ca viet))~".
• Adding a wildcard symbol may retrieve word variants: so sac ky ((lang xa) OR (dang xay)) hoi. hieu ve cac loc may trinh vi ((cua viet) or (ca viet))*.