SharePoint supports document searching out-of-the box, but with some simple customizations, you can greatly improve the findability of documents.
1. Use SharePoint content types.
Content types allow you to segregate your documents and provide document specific meta-data. For example, you can give invoices and purchase orders their own content types and later search on just invoices.
2. OCR images and convert them to searchable PDF.
If you are scanning documents into SharePoint, don’t just store the images. Use scanning software that can automatically create a searchable PDF so that all of the text content of the image can be indexed. The install a free or commercial PDF iFilter as MOSS 2007 does not support indexing PDF documents out of the box.
3. Index your Documents.
Create a taxonomy for each content type and index documents as they are being scanned or saved to SharePoint. Third party software can be used to help index and classify documents as they are being scanned or after they are stored in SharePoint.
4. Display a thumbnail preview in search results.
When viewing search results, it’s important to quickly identify the document you are looking for. Configure search results to show appropriate metadata, and add a thumbnail by using a 3rd party add-on or upgrading to Fast Enterprise Search.
5. Search on specific columns.
Sometimes keyword searches are too broad. For example if you know you are looking for an invoice for a specific customer, you’ll want to direct your search to specific content type columns, not all of the indexed text. Use a 3rd party add-on that supports column-based search.
6. Sort and Filter the results.
If you’ve gotten too many results, you can still find what you need if you can further filter the results or sort them. SharePoint can filter search results out of the box, but you can add result sorting through customizations with SharePoint Designer or third-party add-ons.
7. Use the correct icon for the file type.
In your search results, it’s nice to quickly see what type of documents you have. However, SharePoint only has icons for Office formats. Microsoft KB Article 832809 describes how to customize SharePoint to show the correct icons for all the types you care about.
8. Use Faceted Search.
Faceted search looks at your results and finds categories based on the content types and meta-data. Then, you can filter the results by these automatically determined facets. SharePoint 2010 will include this out of the box, but you can have it now through a free add-on available on CodePlex.