Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
tu sach » su sach, te sach, tu cach
xa dong » ha dong, van dong, lao dong
xa nong » xuat nong, may nong, cua nong
cac tac » cac toc, cac bac, cac dac
ca viet » va viet, co viet, hoa viet
hieu ve » hieu va, hieu van
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
doi ca » doi cua, doi cay, duoi ca
ve cac » va cac, vien cac

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)) ky lang xa hoi. hieu ve cac tac ((xa nong) OR (xa dong)) doi ca viet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) ky lang xa hoi. hieu ve cac tac ((xa nong) or (xa dong)) doi ca viet~".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (thu sach)) ky lang xa hoi. hieu ve cac tac ((xa nong) or (xa dong)) doi ca viet*.