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