Also, when in find mode, lets say I search the portal records for one word. When I do this, it gives me back the ENTIRE portal of information, not just the one portal row containing my searched input. This makes searching in long portals with many rows of info in it useless
Well it's doing what it suppose to do. It's never going to leave you with just one portal row of information. What may be easier is a script that does the following
Set Variable for customer ID, in main table
Set Variable for find criteria (if this is multiple fields we'll have to try something different)
GTRR of a list view of the child records
Enter find mode
Set Field for customer id
Set field for find criteria
Constrain Found set.
These are the basic steps, but there are better ways to do this if you describe what you want to do after you find this record.
Here's what your current method is asking of FileMaker:
"Find all records in the layout's table that have at least one portal record matching this criteria."
If you want to find portal records, other methods need be used. Steve has outlined one method. It's also possible to set up a filtered search portal where you enter information in a field on the layout and the portal filters down to just the related records that pass the criteria specified in the field.
There are several examples of this type of portal in "Adventures in FileMaking #2 - Enhanced Value Selection" that you are welcome to investigate to see if they work for you.