Hi,
first you need get selection parameter and if you parameter is not there in search field then add using add_selection_parameter and then after search remove using coll remove from selection parameter collection.
refre below code
lr_qs ?= me->typed_context->search->collection_wrapper->get_current( ).
* Assign selection parameters to internal table
lr_qs_col ?= lr_qs->get_selection_params( ).
lr_param_ent = lr_qs_col->get_first( ).
WHILE lr_param_ent IS BOUND.
lr_param_ent->get_properties( IMPORTING es_attributes = ls_fields ).
APPEND ls_fields TO lt_fields.
lr_param_ent = lr_qs_col->get_next( ).
ENDWHILE.
READ TABLE lt_fields INTO ls_fields WITH KEY attr_name = 'PROCESS_TYPE' low = 'value'.
IF sy-subrc IS NOT INITIAL.
CALL METHOD lr_qs->add_selection_param
EXPORTING
iv_attr_name = 'PROCESS_TYPE'
iv_sign = 'I'
iv_option = 'EQ'
iv_low = 'value'.
ENDIF.
super class search call
after search call (super class search) remove your parameter
lr_qs_col ?= lr_qs->get_selection_params( ).
lr_param_ent = lr_qs_col->get_first( ).
WHILE lr_param_ent IS BOUND.
lr_param_ent->get_properties( IMPORTING es_attributes = ls_fields ).
IF ls_fields-attr_name = 'PROCESS_TYPE' AND ls_fields-low IS NOT INITIAL.
lr_qs_col->remove( lr_param_ent ).
ENDIF.
lr_param_ent = lr_qs_col->get_next( ).
ENDWHILE.
Regards,
Deepika.