Perhaps you should try some spelling variations:
"dung khoan o snippets" » "dung khoa o snippets", "chung khoan o snippets", "tung khoanh o snippets", "dung khoan so snippets", "dung khoan hoi snippets", "dung khoan mot 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: (((("dung khoan 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: (((("dung khoan o snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung khoan o snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung khoan o snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.