We've got one sturdy Chinese dropshipping company spamming the forums (and posts by them will be removed, of course).
The general answer to your question "how to find a reliable business partner" is to ask them for references. If you select a company to make your website, you ask them what other websites they designed and have a look at them. If you select somebody to do your bookkeeping probably you choose one recommended by someone you know.
Recommendations on a forum like this practically always can't be checked. They might be real, and just as well they might be a scam. Same, by the way, goes for webshops (I'm not accusing yours at all, it's just a general observation).
So the only good way is to talk to their customers before you select one.
Hope this helps.
I presently own a website and am looking for an electronic dropshipper. Every time I find one I have checked out I find several people who say they are a scam don't use them. I presently have gifts and collectibles on my sight but the internet is so swamped they aren't selling much. I thought electronics might sell better. But I keep losing money on bad investments. How do I choose a good company to work with.