BibLaTeX : définir un filtre avec un mot-clé contenant un espace.

\documentclass{article}

\begin{filecontents*}{\jobname.bib}
@online{apqcAPQCProcessClassification2025,
  title = {{{APQC Process Classification Framework}} (PCF)},
  author = {{APQC}},
  keywords = {business process modelling}
}

@book{knuth,
  author       = {Knuth, Donald E.},
  title        = {The {\TeX} book},
  date         = 1984,
  maintitle    = {Computers \& Typesetting},
  volume       = {A},
  publisher    = {Addison-Wesley},
  location     = {Reading, Mass.},
  langid       = {english},
  langidopts   = {variant=american},
  sortyear     = {1984-1},
  sorttitle    = {Computers & Typesetting A},
  indexsorttitle= {The TeXbook},
  indextitle   = {\protect\TeX book, The},
  shorttitle   = {\TeX book}
}
\end{filecontents*}

\usepackage{biblatex}
\addbibresource{\jobname.bib}
% Define biblatex filter.
\defbibfilter{si}{keyword={business process modelling}}%

\begin{document}

test
\nocite{*}
\printbibliography[title={Système d'information},filter={si}]%

\end{document}