Biscuit and Fruit bar

Biscuit noun - Small round bread leavened with baking-powder or soda.

Fruit bar and biscuit are semantically related. In some cases you can replace phrase "Fruit bar" with "Biscuit", this terms are similar.

Fruit bar noun - Cookies containing chopped fruits either mixed in the dough or spread between layers of dough then baked and cut in bars.

Biscuit and fruit bar are semantically related. You can use "Biscuit" instead a noun phrase "Fruit bar".