Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
so sach » so sanh, bo sach, co sach
cam luc » cau luc
va hang » van hang, va nang, va lang
hang di » hang doi, hang vi, hang dien
y nang » ky nang, ly nang, v nang
di cua » dai cua, doi cua, de cua
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: so sach ((y nang) or (van dong)) x hoi. hieu van ((cam luc) OR (cam xuc)) va hang di cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ((y nang) OR (van dong)) x hoi. hieu van ((cam luc) OR (cam xuc)) va hang di cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ((y nang) or (van dong)) x hoi. hieu van ((cam luc) OR (cam xuc)) va hang di cua vat".
• Adding a wildcard symbol may retrieve word variants: so sach ((y nang) or (van dong)) x hoi. hieu van ((cam luc) OR (cam xuc)) va hang di cua vat*.