Perhaps you should try some spelling variations:
vu khach » vu khanh, vu khac, vay khach
hieu van » hieu va, thien van, lieu va
vu sach » vu bach, su sach
nang xa » nang x, lang xa, nang ma
van cau » van dau, van hau, van chat
cau luc » cau truc, cau phuc
va tich » va tinh, va dich
va chua » vua chua, ca chua, va chu
luc va » duc va, tuc va, loc va
va cua » via cua, ca cua, ma cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((vu sach) or (vu khach)) ky nang xa hoi. hieu van cau luc va tich ((va cua) OR (va chua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((vu sach) OR (vu khach)) ky nang xa hoi. hieu van cau luc va tich ((va cua) OR (va chua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((vu sach) or (vu khach)) ky nang xa hoi. hieu van cau luc va tich ((va cua) OR (va chua)) tre".
• Adding a wildcard symbol may retrieve word variants: ((vu sach) or (vu khach)) ky nang xa hoi. hieu van cau luc va tich ((va cua) OR (va chua)) tre*.