wildcard search is not working

[Radha C.]

Hi,
 
 
I have documents contain word "healthcare articles". I need to match the
"healthcare artcles" documents 
for the query strings "helath", "articles"... 
 
I tried q="health*", q=helath*, q="heath*articles" but everything returns
empty result. When I try q="healthcare artilces" ,the search returns proper
documents.
 
Can anyone tell me what is the wrong with my query string?