If you want to narrow down where in the metadata documents Mercury searches in, use Fielded Searches. Pick a topic to search on from the Search Topic pick list. Once picked,the 'text box' beside the pick list becomes active. Enter the text you want to search in that 'text box'. For example, if one picks 'Title' from the pick list, and enter's the term 'Water' in the text box. Then search is made on all the metadata where the Title contains the term 'Water'.