I didn't get a full or partial on my last book, so you're not alone. I think it was the book rather than the query. Admittedly I approached 95% UK agents, so maybe it's different, e.g. I usually sent the first three chapters as part of the submission package. The book being the problem isn't necessarily the worst thing, you can edit and change a book as much as you want after all. I'm not sure polishing a query is the best use of time if the premise isn't exciting anyone. I personally decided to write something else, and while I'm in the very early stages of querying it, and don't yet know if anyone will care for it or not, I'm still really happy I didn't get an agent for my last book and I'm glad I shelved it rather than sent it to everyone possible. It's a little mortifying to not get any interest, but *meh* not every book is great nor exists at a time that it's right for the market.