Does 'Mixing' in bitcoins really add up protection to my bitcoins?
do you mean "anonymize" insteadt of "protect"? if so:

in general: no

everybody can track your bitcoin-transfers on the blockchain. so everybody can theoretically comprehend that you have used a mixer-service. if your mixer-service does really mix your bitcoin, you must still trust your mixer-service that it will never provide some information about that mixing-process in future to anybody. (but maybe this service will be hacked in future or the service must provide some information to a prosecuting authority for example.)

hint: you can improve your anonymity a little bit by changing your bitcoins to a cryotocurrency which has a little bit more anonymity/privacy (for example monero) and then make some transactions and change it back to bitcoin.