Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
luu tre » luu tru, cuu tre, luy tre
vu cham » va cham, vu kham, tu cham
mang xa » mang may, dang xay, mang cua
lang xa » lang ha, dang xay, lang van
xuc van » duc van, luc van, xuc ban
vi luu » vi lua
tu cai » tu cac, tu can, tu bai
cai ky » cao ky, cac ky, cam ky
ve cam » ve cham, ve cac, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu cai ky ((mang xa) or (lang xa)) hoi. hieu ((ve cam) or (vu cham)) xuc van hanh vi luu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cai ky ((mang xa) OR (lang xa)) hoi. hieu ((ve cam) OR (vu cham)) xuc van hanh vi luu tre.
• Adding a wildcard symbol may retrieve word variants: tu cai ky ((mang xa) or (lang xa)) hoi. hieu ((ve cam) or (vu cham)) xuc van hanh vi luu tre*.