Perhaps you should try some spelling variations:
dang xay » dang van, van xay
hanh lai » hanh lam, hanh tai, thanh lap
day hanh » day nhanh, day thanh, dao hanh
cua tre » cua te, cuu tre, cua triet
lai cua » dai cua, hai cua, lai chau
thu day » thuc day, thu da, thu dac
hieu va » lieu va, hieu qua
lang xa » lang ha, lang van
xac ky » cac ky, bac ky
ca thu » cac thu, cam thu, ca tru
sac ky » cac ky, sai ky
va ca » va cac, va cao, va cai

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) OR (sac ky)) ((lang xa) or (dang xay)) hoi. hieu va ca thu day hanh lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((xac ky) OR (sac ky)) ((lang xa) OR (dang xay)) hoi. hieu va ca thu day hanh lai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((xac ky) OR (sac ky)) ((lang xa) or (dang xay)) hoi. hieu va ca thu day hanh lai cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((xac ky) OR (sac ky)) ((lang xa) or (dang xay)) hoi. hieu va ca thu day hanh lai cua tre*.