This is the 15749th most frequent Turkish word.
tezinden
"Tezinden" means "from his/her/its thesis" in English.
In this sentence, 'tezinden' functions as a noun case indicating possession (your thesis) and the source ('from your thesis').
Bu konuda tezinden alıntı yapabilirim.
I can quote from your thesis on this topic.
Here, 'tezinden' denotes a temporal aspect indicating a time before the thesis.
Tezinden önceki taslaklara tekrar göz atmalısın.
You should review the drafts prior to your thesis again.
In this statement, 'tezinden' is used to specify the author of the thesis and indicate the source of learning ('from your friend's thesis').