[TYPO3-english] Exclude typeNum from search results?

[typo3 at wehe-online.de]

Hello,
we use indexed_search and it works fine except for one thing...
We use the extension pdf_generator2 to generate dynamic pdf files of our
website content. These pdf files has the typeNum=123 and are recognized
by indexed_search. This wouldn't be a big thing if the pdf files weren't
the first entries on the search result page.

Does anyone know how I can exclude pdf files (typeNum=123) from the result
page? Thanks!

Jan