Perhaps you should try some spelling variations:
"trong khoa can snippets" » "truong khoa can snippets", "tuong khoa can snippets", "trung khoa can snippets", "trong khoa cam snippets", "trong khoa cap snippets", "trong khoi can snippets"
"dung java java snippets" » "dung va java 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: (((("trong khoa can snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("trong khoa can snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( trong khoa can snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("trong khoa can snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.