Find service`s uuid of a bluetooth device

I'm trying to get information about services provided by bluetooth devices. Using WSALookupServiceNext I can get list of all services. However, regardless of what bluetooth device I try to discover, the resulting WSAQUERYSET structure (pqs) never contains lpServiceClassId field (while the lpszServiceInstanceName is always present). I want to know UUID of a service to determine to which class of the Table 2: Service Class Profile Identifiers it belongs.

#include<winsock2.h>

int main()
{
    WSADATA data;
    WSAStartup(MAKEWORD(2, 2), &data);

    WSAQUERYSET qs{};
    qs.dwSize = sizeof(WSAQUERYSET);
    qs.dwNameSpace = NS_BTH;
    qs.dwNumberOfCsAddrs = 0;
    qs.lpszContext = (LPWSTR)L"12:34:56:78:99:11";
    qs.lpServiceClassId = const_cast<LPGUID>(&PublicBrowseGroupServiceClass_UUID);

    const DWORD flags = LUP_FLUSHCACHE | LUP_RETURN_ALL;
    HANDLE hlookup = nullptr;
    WSALookupServiceBegin(&qs, flags, &hlookup);
    while (true) {
        char buff[4096];
        WSAQUERYSET* pqs = (WSAQUERYSET*)buff;
        DWORD size = sizeof(buff);
        memset(buff, 0, size);

        const INT res = WSALookupServiceNext(hlookup, flags, &size, pqs);
        if (res != 0 && GetLastError() == WSA_E_NO_MORE) {
            break;
        }

        // it prints "service name=Advanced Audio, service uuid=0x0"
        wprintf(L"service name=%s, service uuid=0x%X\n", pqs->lpszServiceInstanceName, pqs->lpServiceClassId->Data1);
    }
}

Answering my own question: In order to get the service ID we have to parse SDP structures which are returned from WSALookupServiceNext function call and accessible via WSAQUERYSET.lpBlob member. For more details see Mike Petrichenko's comment. Also, there is a very good example how to implement it from Qt framework source code.

As for myself, I decided not to follow this path, because my goal was to write a console utility for pairing Bluetooth devices. I have found that there is a better way to do that using Windows.Devices.Enumeration API. Finally, using this API, I managed to create the BluetoothDevicePairing utility I was working on.