Not able to get the crawled properties for managed metadata columns

Hi,

We have two custom columns of type managed metadata for a document library, added some documents to it.
Done the Full crawl and we are able to see the managed metadata columns under Tags section of search results.
we see the crawled properties as ows_taxid_column1, ows_taxid_column2 in dev environment.
We have created a new doc library(not through list defintion) with the above two columns and done the full crawl, but we don't see the crawled propeties for them, have performed full crawl more than 4 times but no luck.

If anyone of you experience this problem earlier, please help me.

Thanks,
Srikanth Sapelly