XSL siblings

i have this problem again but now there's 3 siblings!

example
<SAM>
     <A>
        <AID>xxx</AID>
     </A>
     <B>
        <BID>yyy</BID>
     </B>
     <C>
        <CID>zzz</CID>
     </C>
</SAM>
<SAM> ..... and so on

nows here is my current code:
<xsl:for-each select="SAM">
  <xsl:for-each select="//SAM[A/AID = 'xxx']">
    <xsl:for-each select="B">
        <xsl:if test="BID='yyy' or BID='something'">
                <xsl:value-of select="BID">
--   here is the my problem, i would like to display all CID under
filtered SAM. ---
                 <xsl:for-each select="C"> doesnt work since im
looping a sibling node outside of it,

thanks,
*-::jay::-*