Perhaps you should try some spelling variations:
"using java code snippets" » "using data code snippets", "using java core snippets"
"tran toan hoc snippets" » "tranh toan hoc snippets", "tran tuan hoc snippets", "tran tan hoc snippets", "tran toan khoa snippets", "tran van hoc snippets", "tran hoa hoc snippets"
"locating bug code snippets" » "locating bug core snippets", "locating bung code snippets", "locating bugs code snippets"

Try widening your search to All Fields.

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