Allow me to explain by examples.

Example A:
I enter the search term 'test' (without the apostrophes) and I DO NOT check the 'match whole words only' option. I get the following hits:
- somethinginfronttest
- testsomethingbehind
- test
- [test]
- dbo.test
- dbo.[test]
So far so good, all hits are as expected.

Example B:
I then enter the search term 'test' (without the apostrophes) and I CHECK the 'match whole words only' option. I get the following hits:
- test

And that's it. I do not get the following hits:
- somethinginfronttest
- testsomethingbehind
- [test]
- dbo.test
- dbo.[test]

The first two are as I expect. However, the other three or not.
I would expect (or perhaps I should use the word 'prefer') to also get hits for [test], dbo.test and dbo.[test].

My use case is that often I want to find usages of specific tables or stored procedures.
And sometimes the SQL goes like "LEFT JOIN test", sometimes "LEFT JOIN dbo.test" and sometimes "LEFT JOIN [test]".

If I search using the option 'match whole words only' checked, then I do not get all occurrences.
If I search using the option 'match whole words only' unchecked, then I get way too much occurrences in my case (a huge code base, that has objects like NextTest, TestForThis, TestForThat, etc.).