Perhaps you should try some spelling variations:
hieu thien » hieu hien, chieu chien, dieu khien
thien cac » hien cac, thien cau, thieu cac
thu sach » tu sach, thuat sach, thuoc sach
cua tre » cuu tre, cua triet, dua tren
dinh va » dinh van, dinh ve, tinh va
va dinh » van dinh, va kinh, va tinh
cac lao » ca lao, cac loai, cac giao
su sach » so sach, vu sach
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
lao va » tao va, cao va, bao va
cua te » cua tu

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: ((su sach) OR (thu sach)) ky lang xa hoi. hieu thien cac lao va dinh va ((cua tre) OR (cua te))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (thu sach)) ky lang xa hoi. hieu thien cac lao va dinh va ((cua tre) OR (cua te))~".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (thu sach)) ky lang xa hoi. hieu thien cac lao va dinh va ((cua tre) OR (cua te))*.