Perhaps you should try some spelling variations:
toc sach » doc sach, thuoc sach, nuoc sach
cau tren » cu tren, dau tren, ca tren
hoc sach » hoc sinh, hoc cac, hoc anh
lang xa » lang ha, dang xay, lang van
hieu va » hieu qua
cao suc » cao su, cao duc
va danh » va dinh, va dan, va hanh
danh di » danh du, xanh di, danh dien
v lang » va lang, o lang, _ lang
suc va » duc va, tuc va, luc va
di cau » da cau, diem cau

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: ((toc sach) OR (hoc sach)) v lang xa hoi. ((hieu va) OR (lieu va)) cao suc va danh di cau tren~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) or (hoc sach)) v lang xa hoi. ((hieu va) OR (lieu va)) cao suc va danh di cau tren~".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (hoc sach)) v lang xa hoi. ((hieu va) OR (lieu va)) cao suc va danh di cau tren*.