When performing a search, you may want to seach for multiple values for a particular field. To do this, you first need to specify a field as having a Render Type of “Multi-Select” or “Tags”. Then you can specify multiple comma-delimited values in that field when searching the asset base.
By default, these values will be OR’d together to produce results that meet any of the conditions in the expression. For instance, when searching for the tags “Music”, “Art” as in the example above, the search operation will return results where the Tags field matches “Music” OR “Art” OR (“Music” AND “Art”). This search operation can be changed, however, per field by navigating to Assets | Settings | Data Manager, and then by selecting the “asset” table from the drop-down and selecting the “Customize Fields” tab. Then you can select any field and select a search operation from the “Default Search Operation” drop-down. In particular, notice the “ORs group”,and “AND group” options.
So, for example, if I select “And Group” for the Default Search Operation for the Tags field, the results returned from the search operation are only those that meet the criteria where Tags matches “Music” AND “Art”:
Also, you can specify the Render Type of a field to be “Multi-Select” which allows lists, for instance, to have multiple values: