Please help us to solve the following issue:

The problem is.....
We do not have a specific queue. Default query is  _search?q={$q}
This search query is not getting the result for me.
When we tried different queues, we could not get a good/exact result.

For example: thes query  " ?q=title: iphone 7"

We get the results:

cases iphone 6 64gb
Hoco UltraSlim TPU Case iPhone X
HOCO Light Series TPU for iPhone X - Transparent Black
Monsterskin Super Impact Proof for iPhone X
We want to get the results where you will be able to find the results.

iphone 7  mobile phones.
iphone 7 32gb  mobile phones.  
iphone 7 128gb mobile phones.