I have two:
Providers and Purchasetopay with the following association:
$Providers->hasMany('Purchasetopay', [
   'foreignKey' => 'providers_id'
]);
and I also have the following action:
public function fornecedores(){
        $Providers = TableRegistry::get('Providers');
        $pesquisar = $this->request->query('pesquisar');
        if(!empty($pesquisar)){
            $this->paginate = [
                'conditions' => 
                            [ 'OR' => 
                                ['Providers.cnpj' => $pesquisar,
                                 'Providers.corporatename LIKE' => '%'.$pesquisar.'%',
                                ]                              
                            ]
                         ];
        }
        $query = $Providers->find()->contain(['Telephones','Purchasetopay'=>['SupplierNotes']]);
        $providers = $this->paginate($query);
        $this->set(compact('providers'));
    }
I need to add Purchasetopay field to OR conditions. How?
I saw this solution: https://stackoverflow.com/a/39559315/11239369
However, I don't know how to adapt my code to work this way.