XSL allows combining of conditional statements like other langues. Each one doesn't require its on if statement. Were you thinking something along these lines?
<xsl:choose>
<xsl:when test="contains(text(), 'Service Month/Year:')
or contains(text(), 'Svc Month/Yr:')
">
<!-- do something -->
</xsl:when>
</xsl:choose>
Keep in mind xml/xsl is case sensitive. To make it more flexible, it is even more verbose:
<xsl:variable name="lower" select="'abcdefghijklmnopqrstuvwxyz'"/>
<xsl:variable name="upper" select="'ABCDEFGHIJKLMNOPQRSTUVWXYZ'"/>
<xsl:choose>
<xsl:when test="contains(translate(text(), $upper, $lower), 'service month/year:')
or contains(translate(text(), $upper, $lower), 'svc month/yr:')
">
<!-- do something -->
</xsl:when>
</xsl:choose>
EDIT: And an even better answer I whipped up
<xsl:template name="containsToken">
<xsl:param name="inputString"/>
<xsl:param name="tokens"/>
<xsl:param name="delimiter"/>
<xsl:variable name="lower" select="'abcdefghijklmnopqrstuvwxyz'"/>
<xsl:variable name="upper" select="'ABCDEFGHIJKLMNOPQRSTUVWXYZ'"/>
<xsl:choose>
<xsl:when test="contains($tokens, $delimiter)">
<xsl:variable name="token">
<xsl:value-of select="substring-before($tokens, $delimiter)"/>
</xsl:variable>
<xsl:choose>
<xsl:when test="contains(translate($inputString, $upper, $lower), translate($token, $upper, $lower))">
<xsl:text>True</xsl:text>
</xsl:when>
<xsl:otherwise>
<!-- loop -->
<xsl:call-template name="containsToken">
<xsl:with-param name="inputString" select="$inputString"/>
<xsl:with-param name="tokens" select="substring-after($tokens, $delimiter)"/>
<xsl:with-param name="delimiter" select="$delimiter"/>
</xsl:call-template>
</xsl:otherwise>
</xsl:choose>
</xsl:when>
<xsl:otherwise>
<xsl:choose>
<xsl:when test="contains(translate($inputString, $upper, $lower), translate($tokens, $upper, $lower))">
<xsl:text>True</xsl:text>
</xsl:when>
<xsl:otherwise>
<xsl:text>False</xsl:text>
</xsl:otherwise>
</xsl:choose>
</xsl:otherwise>
</xsl:choose>
</xsl:template>
Usage:
<xsl:variable name="found">
<xsl:call-template name="containsToken">
<xsl:with-param name="inputString" select="text()"/>
<xsl:with-param name="tokens" select="'Service Month/Year:|Svc Month/Yr:'"/>
<xsl:with-param name="delimiter" select="'|'"/>
</xsl:call-template>
</xsl:variable>
<xsl:if test="$found = 'True'">
<!-- process -->
</xsl:if>
Delimiter can be whatever character or charcters you want. Tokens is a list of things to search for with the delimiter between each one. Enjoy!