Webservice does not show return parameters in WSDL

Question

I’m having trouble with a webservice. When accessed its WSDL, the input parameters of the methods appear normally, but the return parameters that each method should show are not appearing. Just for the record, all parameters return a dataset. Could anyone tell me what might be happening? Below the WSDL encoding of the webservice.

<wsdl:definitions xmlns:tm="http://microsoft.com/wsdl/mime/textMatching/" xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/" xmlns:mime="http://schemas.xmlsoap.org/wsdl/mime/" xmlns:tns="http://tempuri.org/" xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/" xmlns:s="http://www.w3.org/2001/XMLSchema" xmlns:soap12="http://schemas.xmlsoap.org/wsdl/soap12/" xmlns:http="http://schemas.xmlsoap.org/wsdl/http/" xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/" targetNamespace="http://tempuri.org/">
<wsdl:types>
<s:schema elementFormDefault="qualified" targetNamespace="http://tempuri.org/">
<s:element name="BuscarMaterial">
<s:complexType>
<s:sequence>
<s:element minOccurs="0" maxOccurs="1" name="codMaterial" type="s:string"/>
<s:element minOccurs="0" maxOccurs="1" name="clientType" type="s:string"/>
</s:sequence>
</s:complexType>
</s:element>
<s:element name="BuscarMaterialResponse">
<s:complexType>
<s:sequence>
<s:element minOccurs="0" maxOccurs="1" name="BuscarMaterialResult">
<s:complexType>
<s:sequence>
<s:element ref="s:schema"/>
<s:any/>
</s:sequence>
</s:complexType>
</s:element>
</s:sequence>
</s:complexType>
</s:element>
<s:element name="AuthHeader" type="tns:AuthHeader"/>
<s:complexType name="AuthHeader">
<s:sequence>
<s:element minOccurs="0" maxOccurs="1" name="UserName" type="s:string"/>
<s:element minOccurs="0" maxOccurs="1" name="Password" type="s:base64Binary"/>
</s:sequence>
<s:anyAttribute/>
</s:complexType>
<s:element name="BuscarFornecedor">
<s:complexType>
<s:sequence>
<s:element minOccurs="0" maxOccurs="1" name="codFornecedor" type="s:string"/>
<s:element minOccurs="0" maxOccurs="1" name="clientType" type="s:string"/>
</s:sequence>
</s:complexType>
</s:element>
<s:element name="BuscarFornecedorResponse">
<s:complexType>
<s:sequence>
<s:element minOccurs="0" maxOccurs="1" name="BuscarFornecedorResult">
<s:complexType>
<s:sequence>
<s:element ref="s:schema"/>
<s:any/>
</s:sequence>
</s:complexType>
</s:element>
</s:sequence>
</s:complexType>
</s:element>
</s:schema>
</wsdl:types>
<wsdl:message name="BuscarMaterialSoapIn">
<wsdl:part name="parameters" element="tns:BuscarMaterial"/>
</wsdl:message>
<wsdl:message name="BuscarMaterialSoapOut">
<wsdl:part name="parameters" element="tns:BuscarMaterialResponse"/>
</wsdl:message>
<wsdl:message name="BuscarMaterialAuthHeader">
<wsdl:part name="AuthHeader" element="tns:AuthHeader"/>
</wsdl:message>
<wsdl:message name="BuscarFornecedorSoapIn">
<wsdl:part name="parameters" element="tns:BuscarFornecedor"/>
</wsdl:message>
<wsdl:message name="BuscarFornecedorSoapOut">
<wsdl:part name="parameters" element="tns:BuscarFornecedorResponse"/>
</wsdl:message>
<wsdl:message name="BuscarFornecedorAuthHeader">
<wsdl:part name="AuthHeader" element="tns:AuthHeader"/>
</wsdl:message>
<wsdl:portType name="SoftExpertSoap">
<wsdl:operation name="BuscarMaterial">
<wsdl:input message="tns:BuscarMaterialSoapIn"/>
<wsdl:output message="tns:BuscarMaterialSoapOut"/>
</wsdl:operation>
<wsdl:operation name="BuscarFornecedor">
<wsdl:input message="tns:BuscarFornecedorSoapIn"/>
<wsdl:output message="tns:BuscarFornecedorSoapOut"/>
</wsdl:operation>
</wsdl:portType>
<wsdl:binding name="SoftExpertSoap" type="tns:SoftExpertSoap">
<soap:binding transport="http://schemas.xmlsoap.org/soap/http"/>
<wsdl:operation name="BuscarMaterial">
<soap:operation soapAction="http://tempuri.org/BuscarMaterial" style="document"/>
<wsdl:input>
<soap:body use="literal"/>
<soap:header message="tns:BuscarMaterialAuthHeader" part="AuthHeader" use="literal"/>
</wsdl:input>
<wsdl:output>
<soap:body use="literal"/>
</wsdl:output>
</wsdl:operation>
<wsdl:operation name="BuscarFornecedor">
<soap:operation soapAction="http://tempuri.org/BuscarFornecedor" style="document"/>
<wsdl:input>
<soap:body use="literal"/>
<soap:header message="tns:BuscarFornecedorAuthHeader" part="AuthHeader" use="literal"/>
</wsdl:input>
<wsdl:output>
<soap:body use="literal"/>
</wsdl:output>
</wsdl:operation>
</wsdl:binding>
<wsdl:binding name="SoftExpertSoap12" type="tns:SoftExpertSoap">
<soap12:binding transport="http://schemas.xmlsoap.org/soap/http"/>
<wsdl:operation name="BuscarMaterial">
<soap12:operation soapAction="http://tempuri.org/BuscarMaterial" style="document"/>
<wsdl:input>
<soap12:body use="literal"/>
<soap12:header message="tns:BuscarMaterialAuthHeader" part="AuthHeader" use="literal"/>
</wsdl:input>
<wsdl:output>
<soap12:body use="literal"/>
</wsdl:output>
</wsdl:operation>
<wsdl:operation name="BuscarFornecedor">
<soap12:operation soapAction="http://tempuri.org/BuscarFornecedor" style="document"/>
<wsdl:input>
<soap12:body use="literal"/>
<soap12:header message="tns:BuscarFornecedorAuthHeader" part="AuthHeader" use="literal"/>
</wsdl:input>
<wsdl:output>
<soap12:body use="literal"/>
</wsdl:output>
</wsdl:operation>
</wsdl:binding>
<wsdl:service name="SoftExpert">
<wsdl:port name="SoftExpertSoap" binding="tns:SoftExpertSoap">
<soap:address location="http://portal.karcher.com.br/softexpert/softexpert.asmx"/>
</wsdl:port>
<wsdl:port name="SoftExpertSoap12" binding="tns:SoftExpertSoap12">
<soap12:address location="http://portal.karcher.com.br/softexpert/softexpert.asmx"/>
</wsdl:port>
</wsdl:service>
</wsdl:definitions>

Thank you.