"Similar hobbies" refers to activities or interests that are alike or similar between two or more people. It means sharing common leisure activities that you enjoy doing with another person or a group. Full definition
I discovered interesting people with similar hobbies as mine and made the first step toward my happiness — I sent messages to a few girls that I liked the most. (russian-woman-dating.com)
This is usually the start of any relationship and then they will try to share similar hobbies with yours. (trusteddatingsiteadvisory.com)
Many people have found this to be a great way to find local people in their area who are interested in similar hobbies, groups, etc.. (lifewire.com)