Sanırım Turkiye´ye döndün?

I thought you were back in Turkey?

Thank you

I think it´s better to say it like this:

Türkiye´ye geri döndüğünü sandım. 

or like this

Türkiye´ye geri döndün sandım. 

What about 

.....Türkiye´ye geri döndün sanıyordum

does this make any sense at all?

That means "I was thinking you were back in Turkey"

zuzu thank you fot your input

and lamda too!