Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"doc 2015 den snippets" » "dong 2015 den snippets", "duoc 2016 den snippets", "nuoc 2015 den snippets", "doc 21 den snippets"
"locating bug code snippets" » "locating bung code snippets", "locating bugs code snippets", "locating bug core snippets"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("doc 2015 den snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("doc 2015 den snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( doc 2015 den snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("doc 2015 den snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.