const GUID CGID_IWebBrowser={0xED016940L,0xBD5B,0x11cf,{0xBA,0x4E,0x00,0xC0,0x4F,0xD7,0x08,0x16}}; 
#define HTMLID_FIND        1

IDispatch* pDocDisp = m_wndHtmlView.GetHtmlDocument();
if( pDocDisp ) {
    IOleCommandTarget *pCmdTarg;
    if( SUCCEEDED(pCmdTarg->QueryInterface(IID_IOleCommandTarget, (void**)&pCmdTarg)) )
    {
        pCmdTarg->Exec(&CGID_IWebBrowser, HTMLID_FIND, 0, NULL, NULL);
        pCmdTarg->Release();
    }
    pDocDisp->Release();
}