Harche proper use

"Harche dur cheshm mitonad bebinad ke hichi nest"

corrected: Ta anja ke cheshm kar mikard, chizi nabud. 

As far as the eye can see there was nothing
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Harche zoodtar inja bar migardi

corrected:Har che zudtar be inja bargard.

"Return here as soon as possible"
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Harche bishtar sai mikoneem sakhter miyofteem

corrected:Har che bishtar sai mikoneem, kamtar ...

You have to fill the blank with a sentence according to the situation you're talking about..

for instance:

Har che bishtar sai mikoneem, kamtar jelo miraveem. (It's about sailing in a river)

Har che bishtar sai mikoneem, kamtar natije migireem. (It's about an chievement in the work, study etc.)

Although what you mean seems a bit different from what I explained, but that was a common structure that I recomended.

However, we have a proverb which seems to be more close to your English sentence, yet it doesn't contain "harche". It is: "yek bar jasti malakhak, do bar jasti malakhak, dafeye sevom mikhory zamin malakhak!!"

In Farsi letters:

یک بار جستی ملخک، دو بار جستی ملخک، دفعه ی سوم میخوری زمین ملخک!!ه

word-to-word translation: "Hey, you little grasshopper!! you jumped once, you jumped twice, but at the third time, you will fall down!!"

"The more we try the harder we fall"

Harche proper use

"Harche dur cheshm mitonad bebinad ke hichi nest" تا جایی که چشم کار میکند چیزی نیست

As far as the eye can see there was nothing

Harche zoodtar inja bar migardi هر چه زودتر برگرد اینجا

"Return here as soon as possible"

Harche bishtar sai mikoneem sakhter miyofteem

"The more we try the harder we fall" هر چه بیشتر تلاش کنیم سختر زمین میخوریم

تو فارسی این ضرب المثل نیست و به جاش میگیم:هر چی سخت بگیری دنیا بهت سخت تر میگیره

That means:if you dont take it easy, the world take it harder for you