Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"dong n1 doc snippets" » "dong 1 doc snippets", "dong nam doc snippets", "dong anh doc snippets", "dong n2 doc snippets", "dong n3 doc 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: (((("dong n1 doc snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dong n1 doc snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dong n1 doc snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dong n1 doc snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.