Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
nhan luc » nang luc
cham luc » cham soc, cham cuu, chat lua
luu tre » luu tru, cuu tre, luy tre
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
sai ky » sac ky
vi luu » vi lua
te sai » te tai, te bai, te lai

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sai ky ((nang xa) or (nang ma)) hoi. hieu ve ((cham luc) or (nhan luc)) van hanh vi luu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sai ky ((nang xa) OR (nang ma)) hoi. hieu ve ((cham luc) OR (nhan luc)) van hanh vi luu tre.
• Adding a wildcard symbol may retrieve word variants: te sai ky ((nang xa) or (nang ma)) hoi. hieu ve ((cham luc) or (nhan luc)) van hanh vi luu tre*.