can I down load Super anti virus spyware tools on top of spyware doctor that is already on my computer?

I know very little about computers But yesterday I go a thing called personal anti virus. Itr gave me fits until I down loaded the Doctor and finally got ridof it. However after some research I found super anti virus and think it may be a better program. I just don`t know if it is wise to down load one on top of the other. Thank you

yes u can also get a-squared both are real good download at filehippo.com

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