Perhaps you should try some spelling variations:
dang xay » dang van, van xay
van hanh » van thanh, ban hanh, van anh
thuc van » thuc vat, thuc dan, thuc va
ve cham » va cham, ve chat, vu cham
mang xa » lang xa, mang may, mang cua
hanh di » hanh vi, hanh de, hang di
di cua » dai cua, doi cua, de cua
su xac » pu xac, su cac
ve cac » va cac, vien cac
xac ky » cac ky, sac ky, bac ky
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: su xac ky ((mang xa) or (dang xay)) hoi. hieu ((ve cham) or (ve cac)) thuc van hanh di cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su xac ky ((mang xa) OR (dang xay)) hoi. hieu ((ve cham) OR (ve cac)) thuc van hanh di cua tu.
• Adding a wildcard symbol may retrieve word variants: su xac ky ((mang xa) or (dang xay)) hoi. hieu ((ve cham) or (ve cac)) thuc van hanh di cua tu*.