Only plain text is supported as of now in the Export to Pdf functionality of an entity.

So, if the entity has a field of type "Multiple Lines of Text" which contains Images, Tables or Rich Text Format are not reflected in the pdf which is generated as part of Export to Pdf functionality (i.e., when we click on Export to Pdf button).

Hence, it would be helpful if Export to Pdf supports Images, Tables or Rich Text Format in near future.