Perhaps you should try some spelling variations:
"quang trung dat snippets" » "truong trung dat snippets", "quang trung dai snippets", "quang trong dat snippets", "quang trung dam snippets"
"using java can snippets" » "using data can snippets"
"locating bug code snippets" » "locating bung code snippets", "locating bugs code snippets", "locating bug core snippets"

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 can snippets") or ("quang trung dat snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using java can snippets") OR ("quang trung dat snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using java can snippets ) or ( quang trung dat snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using java can snippets") or ("quang trung dat snippets"))) or ("locating bug code snippets"))*.