All orders from Holzweiler are shipped with DDP (Delivered Duty Paid).* This means that the cost of customs/tax is included in the price you see during checkout. You will not receive any additional customs or tax after you've placed your order. Read more about DDP and how it affects your shipment here.
DHL might need some help from you (the importer) to clear the shipment through customs. This is just standard procedure, and DHL will in most cases contact you to process the order. Are you having trouble with DHL and customs processing?
*This does not apply to orders being shipped to Switzerland. You will not be charged with EU-VAT during checkout but you will have to pay import taxes to the carrier for the package to be delivered.