I think you can use your original design. Please do not match quotes in quotes. 
  my @quotes = $keyword =~ s/"([^"]*)?"//;
  my @keys = split(/ /, $keyword);

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If you think about spaces at the end or two spaces in the middle modify your code like 
 
  my @keys =grep length, split(/ /, $keyword);

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or
 
  my @keys = split(" ", $keyword);

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In reply to Re: search string regex by Anonymous Monk
in thread search string regex by poprishchin

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