Perhaps you should try some spelling variations:
toc sach » doc sach, thuoc sach, nuoc sach
hoc sach » hoc sinh, hoc cac, hoc anh
hieu van » thien van, lieu va, hieu ve
van hanh » van thanh, ban hanh, van anh
hieu va » lieu va, hieu qua
xuc van » duc van, luc van, vuc van
kem hoa » ket hoa, kim hoa, kien hoa
y nang » ky nang, ly nang, v nang
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((toc sach) OR (hoc sach)) y nang x hoi. ((hieu van) or (hieu va)) cam xuc van hanh kem hoa viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sach)) y nang x hoi. ((hieu van) OR (hieu va)) cam xuc van hanh kem hoa viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (hoc sach)) y nang x hoi. ((hieu van) or (hieu va)) cam xuc van hanh kem hoa viet".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) OR (hoc sach)) y nang x hoi. ((hieu van) or (hieu va)) cam xuc van hanh kem hoa viet*.