Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hanh di » hanh vi, hanh de, hang di
va hanh » van hanh, va thanh, va danh
van dau » phan dau
ly nang » ky nang, ly hang, ly vang
nang o » nang co, nang ho, nang ro
xuc va » duc va, tuc va, luc va
di cua » dai cua, doi cua, de cua
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) OR (toc sach)) ly nang o hoi. hieu ((van dau) or (van dao)) xuc va hanh di cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ly nang o hoi. hieu ((van dau) OR (van dao)) xuc va hanh di cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) ly nang o hoi. hieu ((van dau) or (van dao)) xuc va hanh di cua vat".
• Adding a wildcard symbol may retrieve word variants: ((te sach) OR (toc sach)) ly nang o hoi. hieu ((van dau) or (van dao)) xuc va hanh di cua vat*.