Extract part of a string

Hi guys,

We are trying to extract a part of a string from a textu2019s string like in the following example:

Price (AC)

Quantity (AT)

Material (CS)

u2026u2026.

We want try to extract the text in brackets that has a variable position into the complete string. The result has to be this:

AC

AT

CS

u2026u2026

Does anybody know a standard function to fix this case?

We are waiting an answer, thank you.