my website position frequently changed between 15-29 after google core update

[salume.p]

hello guy,
I have a big problem, after google core update my website position for special keyword frequently change and I don't know what's wrong about my website. problem is about content or backlinks?? anyone can help me, what should I do?
this is my web page : https://bit.ly/2Hh8P5z  and the keyword is "مهاجرت به کانادا"

I would appreciate if you could help me on this matter

[amayajace]

On Monday June 3, 2019, Google announced via Twitter that the update was live and rolling out across Google's data centers: ... This is Google's official broad core update announcement made the day before the update went live: "Tomorrow, we are releasing a broad core algorithm update, as we do several times per year.