Some data, like chat messages or list of contacts can be extracted and exported from phone backups created using the Nokia PC Suite Software. In that case, you can use dedicated converters like the ABC Amber NBU Converter to export certain data from NBU files as PDF documents.
Convert Nokia PC Suite 6.82+ backup to Adobe Portable document format.
We found one software available in the database for this conversion.
Microsoft Windows software - convert nbu to pdf on Windows
A converter utility for NBU backups
Convert from nbu file format
The table with program actions contains information about what each program is capable of doing with their files. This may be a good pointer for further searches for certain file conversions and help you find the converter you are looking for if our search result is insufficient for you. However, it is far from perfect and may sometimes show results which are not really usable because of the nature of the software handles the files. So a conversion that appears as possible, just because of matched actions, may in fact not be possible.