Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"doc sach moi snippets" » "hoc sach moi snippets", "toc sach moi snippets", "nuoc sach moi snippets", "doc sach doi snippets", "doc sach hoi snippets", "doc bach mai 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 sach moi 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 sach moi snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( doc sach moi snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("doc sach moi snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.