Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hanh khu » hanh nhu, hanh phuc, chinh khu
khu cua » hu cua, khi cua, kho cua
va hanh » van hanh, va thanh, va danh
cam duc » cam xuc, cao duc, nam duoc
tu cach » tu cac
te sach » toc sach
cua tre » cua te, cuu tre, cua triet
nang o » nang co, nang ho, nang ro
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: ((tu cach) or (te sach)) ky nang o hoi. hieu van ((cam duc) OR (pham duc)) va hanh khu cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (te sach)) ky nang o hoi. hieu van ((cam duc) OR (pham duc)) va hanh khu cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu cach) or (te sach)) ky nang o hoi. hieu van ((cam duc) OR (pham duc)) va hanh khu cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (te sach)) ky nang o hoi. hieu van ((cam duc) OR (pham duc)) va hanh khu cua tre*.