Possible? Advanced Tooltips

Hey all,
i have a little Problem with the Tooltips.
I give an example:
There is the word “Car” in the Glossary.
Now i have a text on a site like this – “The Cars are fast.”
How can i add the Tooltip to the word Cars? Its Plural but the Glossary Term is singular.
When i change the slug car to cars nothing happens.

I need fast help, so im very happy if someone can explain that to me!

Best regards
Michael

http://ww.wp.xz.cn/plugins/wp-glossary/