-- Example table:

create table patient (
    id serial primary key,
    firstname varchar(100),
    lastname varchar(100)
);

insert into patient(firstname, lastname) values ('MARCO ANTONIO', 'PEREZ SANDERS');

-- Create field tsvector field with text columns (preferable using insert and update trigger);
alter table patient add tsv_name tsvector;

-- initially fill field.
update patient set tsv_name = to_tsvector(firstname || ' ' || lastname);

-- create index for fast search:
create index tsv_name_idx on patient using gin(tsv_name);

-- then you can search as:
select * from patient where tsv_name @@ to_tsquery('MARCO & PEREZ');
select * from patient where tsv_name @@ to_tsquery('MARCO & SANDERS');
select * from patient where tsv_name @@ to_tsquery('ANTONIO & PEREZ');

select * from m_paciente 
where tsv_nombre @@ to_tsquery(array_to_string(string_to_array('LEIRY SEVERINO',' '),':* & ')||':*');

-- other:

select * from patient where fullname ~ all(array['(?=^LEI.*|\s+LEI\w*)','(?=^ME.*|\s+ME\w*)']);