Hey,

I have several books, but here are a few on-line resources I found helpful when i was learning

http://basic-croatian.blogspot.com  

http://www.lztranslation.com/serbian_grammar.html

Ed

It is pretty clear there are there are people on these platforms looking for something other than real language learning. The most common seems to use them as on-line dating platforms. Oddly, I had a case one one platform where they person pretend to be interested in language exchange, only to start asking me for money. As an English native, i frequently get people asking me to help them that don't speak a language I am learning, which is rather one sided, and not in the spirit of "exchange". Lastly, I have found that even among those who speak the languages I am learning, not all are able or willing to focus on helping me progress in their language. They tend to only want to speak English even when I am trying to speak their language. So I think there can be  a multitude of issues that cause frustration.

What I have been doing now is being more selective and slow about who I accept as a language partner. First, I read their profile. A blank profile makes me lose interest. Then I look at their level.. I try to make sure i pick someone at a similar level as I am. My experience is that if one parter is much more advanced, the exchange will probably become a one sided situation. Next thing I do, is I don't commit to a schedule until after I get to know the person. Once I see it is a good match, and they are as willing to help me speak their language as I am willing to help them... then I offer a regular schedule.

So far, I am finding that being cautious as I get to know a new language partner is working pretty well.

There is a book for Russian speakers... In czech it is called "Chcete mluvit cesky". They have prepared it in many languages including Russian. If you search in Russian language on google, maybe you can find it. I used this book to learn Czech. it was very helpful.