You can search for "from:me". For example, this link should show you your own posts from last year: https://plus.google.com/s/from%3Ame%20before%3A2018%2F01%2F

You can search for "from:me". For example, this link should show you your own posts from last year: https://plus.google.com/s/from%3Ame%20before%3A2018%2F01%2F1%20after%3A2017%2F01%2F01/top https://plus.google.com/s/from%3Ame%20before%3A2018%2F01%2F1...