JUST and ONLY

Hello! How is it going? Thanks to everyone for
helping me with my English.

My questions:

1.- Can I use ‘just’ with the meaning
of 'only? in the following sentence:

E.X. He just get money that way (=stealing,
for instance)

2.- Can I omit ‘Only’ in the following sentence?
I think the sentence
seems to be ambiguous if I don?t use it,
not?
Don?t you think it seems that I?m looking
for my biscuits instead of my rubber if
I omit ‘only’? Could ‘ONLY’ be optional?

I?ll open the box to see what is inside.
You say I?ll ‘ONLY’ find my biscuits, but I don?t
believe you. I?m afraid you hid my rubber in
there.

If I made some more mistakes, don?t hesitate to
correct me. I will appreciate it. Thanks a lot!

Jes?s.

Hi Jesus

I’ve written my comments in the quote.

Amy

Hi, Amy!. Well, I am still confused about the difference
between just and only. I think it?s really difficult.
I was writing a sentence this afternoon. It?s
really similar to my previous example.

Take a look!

I am trying to say he/she gets money
lying people, thanks to lie people.

E.X. All your life you?ve been lying (=to lie)
You always hunger for money and
you JUST get it that way (=lying).

Did I use ‘just’ correctly here?

Can I use ‘only’ instead of it and mean
the same thing?

Thanks!

Jes?s