Perhaps you should try some spelling variations:
"duong toan o snippets" » "dung toan o snippets", "duong tan o snippets", "duong tuan o snippets", "duong toan ho snippets", "duong toan co snippets", "duong toan do snippets"
"python using java snippets" » "python using data 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: (((("duong toan o snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("duong toan o snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( duong toan o snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("duong toan o snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.