$ cat search_file.txt
This line contains kwd1.
This line contains kwd2.
This line contains no match.
This line contains no match.
This line contains kwd5.

$ cat search_kwd.sh
grep kwd1 search_file.txt
grep kwd2 search_file.txt
grep kwd3 search_file.txt
grep kwd4 search_file.txt
grep kwd5 search_file.txt

$ sh search_kwd.sh
This line contains kwd1.
This line contains kwd2.
This line contains kwd5.

$ sh search_kwd.sh
This line contains kwd1.
This line contains kwd2.
string
string
This line contains kwd5.