When in the search screens and you are using multiple columns/attributes in your search:
Check the Set Numbers shown in the Set columns are setup correctly for your search.
Columns and attributes are grouped into sets. The Set Numbers indicate which columns/attributes are in the same sets and if the search is using an 'and' statement or an 'or' statement.
The key element to remember here is that to come up in the search result, the record must match one column or attribute from each set.
The actual set number itself has no significance. Columns/attributes assigned a number 1 are not more important than those with a number 2.
If you insert the minus sign (-) before a set number, any record with the associated column/attribute will be excluded from the search results.