Script Search-Display vendor if category is having Tax Agency 'Yes'

hi,

I am creating field 'TaxSupplier' through suitelet of type 'select'

var TaxSupplier = form.addField'wcpayee', 'select', 'Tax Supplier');
populateTaxSupplier(TaxSupplier);

I have written function 'populateTaxSupplier' , where it would search all the vendors whose category having 'Tax agency' yes.

but 'taxagency' is not available in search filter/column for vendorcategory, so how this is possible through script


function populateTaxSupplier(vendordata)
{
var filters = new Array();
filters[0] = new nlobjSearchFilter('isinactive', null,'is','F');
filters[1] = new nlobjSearchFilter('istaxagency', 'vendorcategory','is','T'); - //getting error

var columns = new Array();
columns[0] = new nlobjSearchColumn('internalid');
columns[1] = new nlobjSearchColumn('entityid');

var searchResults = nlapiSearchRecord('vendor', null, filters,columns);

     if(searchResults != null && searchResults != '')