Learn Farsi: می‌خواهم در مورد سیاست بیشتر بدانم.

dar mored-e is a compound preposition used to introduce a theme or topic. It literally translates to "in the case of" or "in the matter of". The invisible -e at the end of mored is the ezāfe, which acts as a bridge linking the preposition to the noun it introduces, which here is siâsat (politics).

Could I use other prepositions like dar bâre-ye or râje' be in this sentence?

Yes, absolutely! dar bâre-ye siâsat and râje' be siâsat both mean "about politics" and are completely interchangeable with dar mored-e here. Just remember that dar bâre-ye uses an ezāfe to connect to the noun, whereas râje' be relies on the simple preposition be to make the connection.

Why does the second verb, bedânam, start with be- instead of mi-?

This is the subjunctive form of the verb. Because the sentence begins with mi-khâham (I want), the action of "knowing" hasn't happened yet; it is just a desire. Farsi shows this by putting the second verb in the subjunctive mood, which usually means replacing the mi- prefix with be-. The literal structure is "I want that I know".

Why is bishtar (more) placed right before the verb, rather than earlier in the sentence?

While Farsi word order can be flexible, adverbs of degree like usually sit immediately before the verb they modify. Since verbs normally go at the very end of a Farsi sentence, it is perfectly natural to say "about politics more I know" ().