If the characters you are trying to print are part of standard PDF fonts, then you may need to switch the PDF engine from the default (“DomPDF”) to a different engine which has support for a wider range of languages (“mPDF”). To do this, additionally install and activate one of these plugins:
- WooCommerce PrintNode mPDF – if you are printing from the built-in “Simple Summary” source.
- WooCommerce PDF Invoices & Packing Slips + mPDF – if you are printing a PDF generated by WooCommerce PDF Invoices & Packing Slips.
If this does not work, then likely you are using a font that is not part of the PDF standard. You should either a) switch to one of the standard fonts or b) follow this FAQ to embed your font.