Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"den hieu doi snippets" » "de hieu doi snippets", "den hien doi snippets", "ten hieu doi snippets", "den hieu moi snippets", "den hieu loi snippets", "den hieu voi 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: (((("den hieu doi snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("den hieu doi snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( den hieu doi snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("den hieu doi snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.