Perhaps you should try some spelling variations:
toc sach » thuoc sach, nuoc sach, toc san
doc sach » nuoc sach, dac sac, bo sach
hoc sach » hoc sinh, hoc cac, hoc anh
tu nang » tru nang, tu nong, tu nano
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
cao tuc » dao tuc, cao duc, cao suc
xa hanh » xa thanh, xa khanh, va hanh
cua tre » cua te, cuu tre, cua triet
va cao » va cac, va co, va dao
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: ((((toc sach) OR (doc sach))) or (hoc sach)) tu nang xa hoi. hieu va cao tuc xa hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((((toc sach) OR (doc sach))) OR (hoc sach)) tu nang xa hoi. hieu va cao tuc xa hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((toc sach) OR (doc sach))) or (hoc sach)) tu nang xa hoi. hieu va cao tuc xa hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((((toc sach) OR (doc sach))) or (hoc sach)) tu nang xa hoi. hieu va cao tuc xa hanh vi cua tre*.