Perhaps you should try some spelling variations:
"co trinh thiet snippets" » "co trinh viet snippets", "co trinh thi snippets", "co tranh thiet snippets", "cong trinh thiet snippets", "tao trinh thiet snippets"
"using java core snippets" » "using data core snippets"
"locating bug code snippets" » "locating bung code snippets", "locating bugs code 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 core snippets") or ("co trinh thiet snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using java core snippets") OR ("co trinh thiet snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using java core snippets ) or ( co trinh thiet snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using java core snippets") or ("co trinh thiet snippets"))) or ("locating bug code snippets"))*.