Column modify width for each search

roni_cec

I realized something strange ...
Every time I perform a dynamic search the column of my table is decreasing ...
To illustrate my question, below I will put a picture of the first research I do, you may notice that the buttons are all lined up properly ...

First Image:
https://www.dropbox.com/s/6a3wqbvetkgz5m9/Captura%20de%20tela%202015-05-30%2012.34.19.png?dl=0

After some research looks like this:
https://www.dropbox.com/s/ljum8c6ftycbecj/Captura%20de%20tela%202015-05-30%2012.35.08.png?dl=0

My function dynamic is:

tabelaDinamica: function(tabela,url,acao,variaveis,colunaOrderBy, tipoOrderBy){

     //Funcoes.mostrarLoading();
     var url = url;
     url += "?acao="+acao;
     //percorrer variaveis
     if(variaveis.length > 0){
       $.each(variaveis,function(i,obj){
          url += "&"+obj[0]+"="+obj[1];
       });
     }
     //ordenar tabela pela coluna
     colunaOrderBy = colunaOrderBy != '' ? colunaOrderBy : 1;
     tipoOrderBy = tipoOrderBy != '' ? tipoOrderBy : 'desc';

     var oTable = $("#"+tabela).dataTable( {
             "language": {
                 "url": "http://cdn.datatables.net/plug-ins/9dcbecd42ad/i18n/Portuguese-Brasil.json"
            },
            destroy: true,
            "order": [[ colunaOrderBy, tipoOrderBy ]],
            "bProcessing": true,
            "serverSide": false,
            "sAjaxSource": url,
            "sDom": "<'row'<'col-sm-6'l><'col-sm-6'f>r>t<'row'<'col-sm-6'i><'col-sm-6'p>>",
            "sPaginationType": "full_numbers"            
        });
     //Funcoes.esconderLoading();
    
  }