Perhaps you should try some spelling variations:
"using java code snippets" » "using data code snippets", "using java core snippets"
"duong thuy do snippets" » "duong thu do snippets", "duong thi do snippets", "duong huu do snippets", "duong thuyet do snippets", "duong thay doi snippets", "duong thuat do snippets"
"locating bug code snippets" » "locating bug core snippets", "locating bung code snippets", "locating bugs code 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: (((("using java code snippets") or ("duong thuy do snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using java code snippets") OR ("duong thuy do snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using java code snippets ) or ( duong thuy do snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using java code snippets") or ("duong thuy do snippets"))) or ("locating bug code snippets"))*.