strawberry in jam

[Ju]

This kind of jam in strawberry flavour get a lot of strawberry inside. (not a fresh strawberry)

What should I say that strawberry in jam?

Thank you.

[JMurray]

Ju.
I'm not sure exactly what your question is but the sort of jam you describe is called "strawberry jam" and if you want to say that it has a lot of strawberries in it: "This jam is packed with strawberries", "... has plenty of strawberries", "... is full of strawberries".

not a teacher

[The Dude]

I agree.

Also, for labels on jam-jars, we use 'High Fruit Content', also 'Extra Fruit', or this piece of Euro-nonsense: 'Extra Jam'.

The first two are accurately descriptive, telling us that there are lots of strawberries in this jam.

The third is nonsense because it implies that there is extra jam in the jar, which there isn't. However I believe it is now the officially-required description.

[Tdol]

this piece of Euro-nonsense: 'Extra Jam'.

I think you meant to say the European Union Jam Directive (Council Directive 79/693/EEC, 24 July 1979), not Euro-nonsense. A fascinating read, I imagine.