Node is getting splitted in case of if statement

If in Syntax Editor we write an if statement like the following:

if(true AND false)

{

}

Then, the ICompilationUnits are generated by the Function FindAncestor and the node inside the if statement's expression splitted and two errors are shown

1. ) expected

2. ; expected

But We want to generate a custom error message in case AND/OR is written in Syntax Editor instead of the above mentioned messages. But We are not getting the "true AND false" as a Node.

How could we get the Node without getting splitted so that we can generate our error message ?