Perhaps you should try some spelling variations:
toc sach » hoc sach, thuoc sach, nuoc sach
van hanh » van thanh, ban hanh, van anh
doc sach » hoc sach, nuoc sach, dac sac
ly nang » ky nang, ly hang, ly vang
nang co » nang cao, nang doc, nang noi
hieu va » lieu va, hieu qua
cac xuc » cam xuc, cac nuoc, chat xuc
xuc van » duc van, luc van, vuc van
tai cua » thai cua, tai cuc, dai cua
co hoi » co hoc, co loi

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)) ly nang co hoi. hieu va cac xuc van hanh ((tai cua) OR (tri cua)) tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (doc sach)) ly nang co hoi. hieu va cac xuc van hanh ((tai cua) OR (tri cua)) tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) or (doc sach)) ly nang co hoi. hieu va cac xuc van hanh ((tai cua) OR (tri cua)) tu".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (doc sach)) ly nang co hoi. hieu va cac xuc van hanh ((tai cua) OR (tri cua)) tu*.