Hi Matheus,
Your SOAP request should look something like this:
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:ser="http://www.ca.com/UnicenterServicePlus/ServiceDesk">
<soapenv:Header/>
<soapenv:Body>
<ser:doSelect>
<sid>123456789</sid>
<objectType>nr</objectType>
<whereClause>name='put the right name here'</whereClause>
<maxRows>-1</maxRows>
<attributes>
<!--1 or more repetitions:-->
</attributes>
</ser:doSelect>
</soapenv:Body>
</soapenv:Envelope>
As you can see, the object type is "nr" which refers to the Configuration Item object in Service Desk. This is the raw SOAP request, so if you are writing a program to make this call, then that would look a little bit different, but the attributes (sid, objectType, whereClause, and maxRows) should be the same.
Please let me know if you have any more questions!
-Marty