Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
vu sach » vu bach, su sach, vu khach
sach le » cach le, sach de, sach lo
le lang » le tang, le dang, le xang
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
va cam » va cham, va cac, va cao
luc va » loc va
tuc va » thuc va, truc va, tuc xa
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: vu sach le lang xa hoi. hieu va cam ((((luc va) OR (duc va))) or (tuc va)) hanh vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach le lang xa hoi. hieu va cam ((((luc va) OR (duc va))) OR (tuc va)) hanh vi cua viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach le lang xa hoi. hieu va cam ((((luc va) OR (duc va))) or (tuc va)) hanh vi cua viet*".