Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"lan van cong snippets" » "lan van dong snippets", "lan van phong snippets", "lan phan cong snippets", "luan van cong snippets", "lang van cong snippets", "tan van cong 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: (((("lan van cong snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("lan van cong snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( lan van cong snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("lan van cong snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.