Findall:

This function will search for all occurrences of a substring in all
selected sequences.  If searching in DNA or RNA sequence, the search
uses IUPAC ambiguity codes. Otherwise, only exact matches are used.
The characters '-' and '~' are ignored in the search so that alignment
gaps do not interfere with the searches.

The search can be case sensitive, as well as allowing for a percentage
mismatch.

The results are passed back as a set of color masks that are automatically
overlaid on the sequences.  Use the File:Properties... menu to disable
the color mask, and return the standard character->color display.