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