Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"hieu moi do snippets" » "nhiem moi do snippets", "hieu so do snippets", "hieu bo do snippets", "hieu moi doi snippets", "hieu moi co snippets", "hieu moi de 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: (((("hieu moi do snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("hieu moi do snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( hieu moi do snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("hieu moi do snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.