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