Have you tried online dating without success? Your profile might be one reason why you didn't get any responses. Since profile space is limited in the online dating world, you have to make sure what you put up there gives a potential date a taste of who you really are. Here are some common phrases to avoid using.
I see this a lot especially on midlife dater's profiles, and I suspect it's because we've been out in the world of dating and romance a long time and have the attitude that we're not going to waste our time if things aren't going to go anywhere.
However, saying this in a profile makes you seem desperate for a relationship, not cautious or mature. You need to spend time getting to know someone to see if they're "serious" or not. You can't call them out about it on a profile.