Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
thu sach » thuat sach, thuoc sach, thu hoach
hieu cua » hieu qua, dieu cua, bieu cua
cua coc » cua cac, cua co, cua hoc
tu sach » su sach, te sach, tu cach
v nang » va nang, vu nang, van nang
y nang » ky nang, ly nang, may nang
luc ca » luc cao, luc cua, luc va
ca dan » cac dan, ca dao
dan va » doan va, dan ca, ban va
va cua » va chua, via cua, ca cua

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ((y nang) OR (v nang)) xa hoi. hieu cua coc luc ca dan va cua viet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thu sach)) ((y nang) OR (v nang)) xa hoi. hieu cua coc luc ca dan va cua viet~".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) ((y nang) OR (v nang)) xa hoi. hieu cua coc luc ca dan va cua viet*.