Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
sach ky » sac ky, sach y, sach ty
va hanh » van hanh, va thanh, va danh
so sach » so sanh, bo sach, co sach
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
va cai » va cac, va bai, va dai
ve tai » te tai, de tai, le tai
ve cac » va cac, vien cac
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: so sach ky lang xa hoi. hieu ((((va cai) or (ve tai))) or (ve cac)) luc va hanh vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky lang xa hoi. hieu ((((va cai) OR (ve tai))) OR (ve cac)) luc va hanh vi cua viet.
• Adding a wildcard symbol may retrieve word variants: so sach ky lang xa hoi. hieu ((((va cai) or (ve tai))) or (ve cac)) luc va hanh vi cua viet*.