Nested Or And AND Conditions For The Same Column

Hello,

I would like some assistance with some code that I am attempting to write. I have one column (Mgr1FullName) that contains different values. I want it to show me all the people who has a manager name as Unavailable, Null, or blank.

Example Code:
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select uuid_hdr.id,
uuid_hdr.bizrightid,
uuid_hdr.fullname,
uuid_hdr.mgr1fullname,
uuid_dtl.role,
uuid_dtl.application,
uuid_dtl.dateremoved,
uuid_dtl.userid

from uuid_dtl
inner join uuid_hdr
on uuid_dtl.hdr_id = uuid_hdr.id
where uuid_dtl.dateremoved is Null and
uuid_dtl.application = 'SAPRET'and
uuid_hdr.mgr1fullname = 'Unavailable'or
uuid_hdr.mgr1fullname is Null or
uuid_hdr.mgr1fullname = ' ' and
uuid_dtl.userid not like 'prodsup%' and
uuid_hdr.bizrightid not like 'prodsup%' and
uuid_dtl.role not like 'z:m_genuser_vendor'
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Should I use ORs or ANDs? I will face this same problem with the ROLE column.

Thanks for all and any help.

Twyn