Perhaps you should try some spelling variations:
vu khach » vu khanh, vu khac, vay khach
van lang » van nang, va lang, van hang
nhan luc » nang luc
su sach » so sach, vu sach
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
va nhan » van nhan, ca nhan, va phan
va hanh » van hanh, va thanh, va danh
luc va » duc va, tuc va, loc va
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) or (vu khach)) van lang xa hoi. hieu va nhan luc va hanh vi cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu khach)) van lang xa hoi. hieu va nhan luc va hanh vi cua vat.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (vu khach)) van lang xa hoi. hieu va nhan luc va hanh vi cua vat*.