What is harder for a patient to fix with schizophrenia: positive or negative symptoms?

Positive. Typically it is considered to be easier to treat the positive symptoms of schizophrenia as opposed to the negative symptoms. Positive symptoms tend to respond better to antipsychotic medications. Medications to treat the negative symptoms of schizophrenia are currently lacking or of limited efficacy.
Negative. Our treatments for schizophrenia are generally less effective, although still beneficial, for negative symptoms. Sadly, negative symptoms often account for the majority of functional impairment from schizophrenia.