# Biblatex multible bibliographies using keywords not working

I'm trying to print a sperate bibliography for references for figures but only one of the bibliographies prints at the end of the document.

Warnings in the document:

Keyword 'primary' not found on input line 8.
Empty bibliography on input line 8.


Minimal working example:

\documentclass{article}
\usepackage{biblatex}

\begin{document}
Hello\cite{KandR} and Goodbye\cite{CUEDCplusplus}

\printbibliography[keyword=primary, title={Primary references}]
\printbibliography[notkeyword=primary, title={Other references}]
\end{document}


bib.bib

@book{KandR,
author  = {Kernighan, Brian W. and Ritchie, Dennis M.},
title  = {The C Programming Language Second Edition},
publisher = {Prentice-Hall, Inc.},
year = {1988}
}

@online{CUEDCplusplus,
keyword={primary},
author  = {Love, T.P.},
title   = {CUED C++},
url = {http://www-h.eng.cam.ac.uk/help/tpl/languages/C++.html},
urlyear = {2010}
}


Screenshot of the result

That should be keywords (with s!) in the bib-file:
 keywords={primary}

• Just in case it helps someone: I seem to have noticed that if you have several keywords and they are separated by a semicolon, or some by semicolon and some by commas, biblatex will ignore the keywords field and print the entry regardless of \printbibliography's option. Mind those separators! – Juan del Acebo Dec 11 '16 at 15:00