Using a function in different schemas

Hello everyone! This is the first time I post on this list. Until now,
I was able to get a solution to all the problems I had, but now I am
facing an issue I can't resolve, so I hope you can help me.

The problem goes like this: I am using the same distribution of
tables/functions into different schemas, so I have the following
layout
- "schema1" has tables "myTable1" and "myTable2", and function "myFunction"
- "schema2" has tables "myTable1" and "myTable2", and function "myFunction"

Until now I used the full names to distinguish between schemas, like
this: schema1.myTable1 and schema2.myTable1.
But now I have to add an update trigger in both "myTable1" that calls
to a function that makes a select statement on "myTable2".
The problem is that even if the trigger is inside "mySchema1", it
can't find "myTable2" and I don't know how to get the schema that the
function is into.

Things I have tried so far:
- current_schema() but, according to the documentation, it "returns
the name of the schema that is first in the search path" and that is
neither "mySchema1" or "mySchema2".
- Passing a parameter to the trigger: since it is an update trigger I
haven't found a way to pass parameter to it.

Can anyone please point me in the right direction?

Thanks in advance!
Juan M.