I find formatting can help. List each of your questions at the bottom of your emails, so they can go through them and answer them one by one. It's also harder for them to justify answering one question and ignoring the rest when you lay it out for them in one place.
Depending on the questions and how much the answers matter, it may be better to ask each one after they reply to the previous one, so they don't feel overwhelmed being asked all of it at once and put more thought into answering each one.
It shares proven email templates to get clients, ask for referrals, etc.
Yes there are a lot of templates out there, but 95% of them sound template-y and could probably pass a reverse Turing test.
I find the key to what makes an email work is both in the ask and how you say it (sounding human sounds like it should be second-nature, until we find ourselves typing into that box with a goal to convince someone or sell something).
Depending on the questions and how much the answers matter, it may be better to ask each one after they reply to the previous one, so they don't feel overwhelmed being asked all of it at once and put more thought into answering each one.