I'm not sure why you've been downvoted, as your question looks like an honest one, and the answers are very informative. I certainly learned something new from the replies. Thanks for asking!
The black magic of a hydrogen bomb is that it focuses the explosive energy of a fission bomb to ignite a fusion explosion. Doing so requires a very specific configuration; any hydrogen on the outside of the bomb, regardless of its concentration, would not reach the appropriate temperature/pressure to fuse.
XKCD 10,000: https://xkcd.com/1053/
Edit: now I'm puzzled why this is collecting downvotes. :-)