Perhaps you should try some spelling variations:
hieu cua » hieu qua, dieu cua, bieu cua
cac luoc » cac nuoc, cac cuoc, cac quoc
luoc van » luoc can, luoc va, luc van
van hanh » van thanh, ban hanh, van anh
lang xa » lang ha, dang xay, lang van
hanh di » hanh vi, hanh de, hang di
sac ky » sai ky
cua te » cua tu
cua cu » cua chu, cua cau, cua su

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sac ky) or (cac ky)) lang xa hoi. hieu cua cac luoc van hanh di ((cua te) or (cua cu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sac ky) OR (cac ky)) lang xa hoi. hieu cua cac luoc van hanh di ((cua te) OR (cua cu)).
• Adding a wildcard symbol may retrieve word variants: tu ((sac ky) or (cac ky)) lang xa hoi. hieu cua cac luoc van hanh di ((cua te) or (cua cu))*.