Using Percent Sign In Variable

I am trying to use this command to change the variable in where clause each time:

psexec servername -E cmd.EXE /c "sqlcmd -S servername /E -d dbname -v entertext="'%anything%'" -i c:myfoldermyscript.sql -o c:mypathoutput.sql"
myscript.sql is like:
select * from table_name
where summary like $(entertext);

This command works just for variables with single and exact word. It does not work for variables which has space between them or when I enter part of summary.In fact, I wanted to write something which the user be able to enter variable each time when he/she run this batch file. because I put this sqlcmd command in batch file( like this in oracle: "select * from table_name where summary = &entertext; " I was looking the same command in sql server , but I did not find it). I do not know .net or any other programing language( I know just csh and command line). I want to do this just with sql command.