Perhaps you should try some spelling variations:
su sach » so sach, vu sach
ky dang » ky nang, ky danh
hieu va » lieu va, hieu qua
va tinh » may tinh
vai cua » dai cua, hai cua, lai cua
_ dang » _ dan, 2 dang, _ danh
va coc » va cuoc, va cac, va hoc
luc va » duc va, tuc va, loc va
vi 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 ((ky dang) or (_ dang)) xa hoi. hieu va coc luc va tinh ((vi cua) OR (vai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ky dang) OR (_ dang)) xa hoi. hieu va coc luc va tinh ((vi cua) OR (vai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ky dang) or (_ dang)) xa hoi. hieu va coc luc va tinh ((vi cua) OR (vai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: su sach ((ky dang) or (_ dang)) xa hoi. hieu va coc luc va tinh ((vi cua) OR (vai cua)) tre*.