Making distance/space between notes above a syllable smaller

[b.a.g.hillen]

Is it possible in Lilypond to make the distance/space between two or three notes above a syllable smaller?

In the example see the slurs g(bes) and bes(c bes) with 2 or 3 notes.

\version "2.18.2"

eenVoice = \relative c'' {\key bes \major

   \cadenzaOn   % zet barlines uit

   \override Staff.TimeSignature #'stencil = ##f

   \hide Stem

   d,4 f g f g (bes) bes^- bes (c bes) a g^- \bar":|."

}

verseOne = \lyricmode {

    O -- ver heel de aar -- de klinkt hun roep.

}

\score {

  <<

    \new Voice = "one"  {

    \eenVoice

}

    \new Lyrics \lyricsto "one"{

    \verseOne

}

  >>

}

Regards,

Ben Hillen