how can i minimize the my select.give me any solution please

It looks like the differences between each union query is the combination of exists and not exists, why?

A similar query could be

SELECT pa_num,
partner_id,
product_line
FROM IF_LSP_PANUM_MAP ilp
WHERE icp.country_code=i_workflow_keys
MINUS
SELECT pa_num,
partner_id,
product_line
FROM IF_LSP_PANUM_MAP ilp
WHERE icp.country_code=i_workflow_keys
AND EXISTS(SELECT 1
FROM sq_partner partner, sq_lsp lsp
WHERE partner.partner_id = lsp.company_id
AND partner.country_code =ilp.country_code
AND partner.partner_id=ilp.partner_id
AND partner.active = 'Y'
)
AND EXISTS(SELECT 1
FROM sq_product_line pl
WHERE pl.PRODUCT_LINE_ID=ilp.product_line
)

Or

with ipl as (SELECT pa_num,
partner_id,
product_line
FROM if_lsp_panum_map ilp
WHERE icp.country_code=i_workflow_keys
)
SELECT pa_num,
partner_id,
product_line
FROM ilp
MINUS
SELECT pa_num,
partner_id,
product_line
FROM ilp
WHERE EXISTS(SELECT 1
FROM sq_partner partner, sq_lsp lsp
WHERE partner.partner_id = lsp.company_id
AND partner.country_code =i_workflow_keys
AND partner.partner_id=ilp.partner_id
AND partner.active = 'Y'
)
AND EXISTS(SELECT 1
FROM sq_product_line pl
WHERE pl.PRODUCT_LINE_ID=ilp.product_line
)

So the access on if_lsp_panum_map is done once (if the CBO decides it should materialize the CTE)

As EXISTS,EXISTS is the only combination of existence checks that doesn't exist in your query.

How do you optimize that? Who knows?! You could delete all your rows in IF_LSP_PANUM_MAP, that would probably speed it up! Without knowing the distribution of your data, your requirements, your table definitions, it's impossible to help. Connor has provided you the easiest way of seeing where the time goes and what (if any) mistakes the optimizer has made, this will show you very clearly what steps you could take.

You'll have to decide (using your knowledge of your data) where the query should drive from, should it check every row in if_lsp_panum_map that fits your country_code predicate for existence in the other tables? Or should it figure out what values of product_line and/or partner_id and country_code it needs to look for in if_lsp_panum_map. The answer depends on how selective the filter is and how much work needs to be put in to finding the value. As usual, given enough information, the CBO will be able to make that decision for you just fine. You may find that due to the highly selective nature of your filters (country_code sounds like you want everything from one country, sounds like a lot of data to me) that full table scans and hash semi joins are the only appropriate way for the query to execute.