Perhaps you should try some spelling variations:
"toc van hoan snippets" » "toc van code snippets", "toc van hoang snippets", "toc van hoa snippets", "toc van toan snippets", "hoc van hoan snippets", "toc san hoan snippets", "tac van hoan snippets"
"locating bug core snippets" » "locating bug code snippets"
"python using java snippets" » "python using data 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: (((("python using java snippets") or ("toc van hoan snippets"))) or ("locating bug core snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("python using java snippets") OR ("toc van hoan snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( python using java snippets ) or ( toc van hoan snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("python using java snippets") or ("toc van hoan snippets"))) or ("locating bug core snippets"))*.