Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"van toan doi snippets" » "van tuan doi snippets", "van tan doi snippets", "van thanh doi snippets", "van toan roi snippets", "van toan dai snippets", "van hoan doi 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: (((("van toan 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: (((("van toan doi snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( van toan doi snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("van toan doi snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.