I was trying to understand how ´yani´ and ´falan´ are used in some examples. They seem to be popular words in conversation.

From my experience, I think filan gives the meaning of "blah, blah" in English. It doesn´t really mean anything. 

Some examples: kitap filan aldım (I think filan in this sentence means, " I bought books & things like that")

                               Öyle bir şeyler konuştuk filan falan.  (I think this means, "yeah we talked like that and blah blah")

As far as yani:

I think it gives the meaning in English,  as "because" or "you see" 

for example i overheard a conversation the woman said 

Istanbuldaki meyveler antalyadan çok pahalıymış

and the woman replied with :yaniii 

So I think it also gives the mean of "i know right." Like your sorta agreeing with the person´s point. 

Anyway I could be wrong, I´d like to hear a natives perspective on it. 

My understanding is

yani = that is to say, I mean, in other words, i.e.

I hear it used a lot in daily conversations with explanations, often when people pause when they are thinking about how to say or explain something. Sometimes like English speakers who use ´um´ while pausing in a sentence

falan (arabic origin) has several meanings and the meanings change with usage.

Here are a few examples from my dictionary

Sekiz kişi falan geldi (Eight people or so came)

On beş ağustosta falan olacak (It will be around the 15th August)

Ali, Nuri, Ahmet falan geldiler (Ali, Nuri, Ahmet and company have come)

When used with filan, falan filan = things like that, blah blah, etc

I just learned that yani can also mean ´so´

For example you´ll hear sometimes: nasıl yani? 

That can mean, how come, or also how so. 

How about this - you don´t want to go into detail about what you are doing today.

Q. What are you doing today?

Bugün napiyorsun?

A. Uhhh, stuff...

Uhhh, falan...

yani = Means, also means "So!" Nasıl yani = How so (Arabic Origin)

Falan = Somthing like | Whatever | Something Undefined | About | around |

Unspecified Thing of number. (Arabic Origin)

Yani has an arabic origine (It´s a verb in arabic) it´s litteraly "it means", Turkish people use it like arab people to explain more somethings said (the 1st sentence)

Hi raydin,

"Yani" sometimes used for "of course - tabi ki" when something is too obvious and especially when pronounced in a longer manner.

Everybody in Turkey knows that İstanbul is the most expensive city and Antalya is tomato producing city.