Both "," and ";" are used in SharePoint as delimiters.
- Is your column a multi-valued Choice or other column?
- In your SharePoint installation, is the list separator a "," or a
";"?
In a Single Line of Text column test that I just did, the semicolon is behaving as a delimiter wildcard. It finds ",", ";", " " and other word delimiters, and is behaving as an AND.
Searching for 555;777
finds:
555,777
555 777
555;777
and, searching for 777;555
finds the same items:
555,777
555 777
555;777
I'm going to do some more test and post back what I find.
After some more testing, I'm guessing that your column is a checkboxed Choice column (or other multi-select column). The semicolon is the default delimiter used to separate the selections and is not part of the data.
I could not duplicate your issue with a Single Line of text column that used a semicolon in the text. But, I did discover an interesting search feature... The semicolon serves as an AND for multiple words in the same field!

When searching for two words, and only one exists, no items are returned.
