Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"van tuan cn snippets" » "van quan cn snippets", "van ban cn snippets", "anh tuan cn snippets", "van tuan cu snippets", "van tuan anh snippets", "van xuan can 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 tuan cn 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 tuan cn snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( van tuan cn snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("van tuan cn snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.