Click HTML button that has ID and Onclick via VBA

I'm trying to click on a button after inputing data in this field:

<input name="termoBuscaUsuarioAprovador" id="termoBuscaUsuarioAprovador" 
style="width: 240px;" onkeydown="javascript:var keyCode = event.keyCode ? 
event.keyCode : event.which ? event.which : event.charCode; if(keyCode == 13) { 
document.getElementById('buscaResponsavel').focus(); }" onkeypress="return 
desabilita(this, event);javascript:var keyCode = event.keyCode ? event.keyCode 
: event.which ? event.which : event.charCode; if(keyCode == 13) { document.getElementById('buscaResponsavel').focus(); }" type="text" value="">

I'm using this and it seems to work:

IE.Document.getElementById("termoBuscaUsuarioAprovador").Value = "xxxxxxx" 'Name

But when I try to click on the "Search" button below, a brief loading bar appears (exacly as if I was manualy clicking the button), but it doesn't show anything, it still remaings blank.

<input name="buscaUsuarioAprovador" id="buscaResponsavel" style="width: 100px;" onclick="pesquisar_dadosUsuarioAprovador(document.getElementById('termoBuscaUsuarioAprovador').value)" type="button" value="Buscar">

The code I'm using that makes the loading bar appears is:

IE.Document.getElementById("buscaResponsavel").Click

I don't know if i'm partially triggering the button because of that "onclick", or if it has something to do with the input field.

Thank you!