The Allow Cross-field Matches option, in the Search Interface editor, specifies when the MDEX Engine should try to match search queries across dimension or property boundaries, but within the members of the search interface.
There are three possible values:
The MDEX Engine always looks for matches across dimension or property boundaries, in addition to matches within a dimension or property. This is the default.
The MDEX Engine does not look across dimension or property boundaries for matches.
The MDEX Engine only tries to match queries across dimension or property boundaries if it fails to find any matches within a single dimension or property.