You have to work with lots of information and texts so you need a powerful tool to search for needed information and other stuff? Try SeachInform. It is a full-text document search application that combines phrasal search with the consideration of morphology and synonyms thesaurus with searching documents similar by content.

The application is designed for fast search of information on PC at large data levels and supports nearly any text formats (txt, doc, rtf, pdf, htm, html) and various data sources. Searching documents similar by content involves the whole plurality of words used in the document with the consideration of all word forms and synonyms. The search can be pin-pointed with the help of `important words` that the application will take into account in the first place and do an additional analysis of documents similarity.

It’s a great tool, but I guess not that affordable – to buy fully operational application you’ll have to spend nearly 50 USD of your companies or your own money.