Keep tiny characters.
[read/write property] keepTinyChars([out, retval] VARIANT_BOOL *keep) keepTinyChars([in] VARIANT_BOOL keep)
By default, XpdfText will discard tiny (smaller than 3 point) characters after the first 50,000 per page. This avoids problems with slow run times due to PDF files that use special fonts to do shading or cross-hatching. Setting this property to true disables this behavior and tells XpdfText to keep all characters.

This setting is global - it applies to all PDF handles.

pdf.keepTinyChars = True