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SELECT * FROM table WHERE pole LIKE '%kusok_slova%'

http://dev.mysql.com/doc/mysql/en/String_comparison_functions.html

Pattern matching using SQL simple regular expression comparison. Returns 1 (TRUE) or 0 (FALSE). If either expr or pat is NULL, the result is NULL. With LIKE you can use the following two wildcard characters in the pattern:
Character Description
% Matches any number of characters, even zero characters
_ Matches exactly one character

mysql> SELECT 'David!' LIKE 'David_';
-> 1
mysql> SELECT 'David!' LIKE '%D%v%';
-> 1

To test for literal instances of a wildcard character, precede the character with the escape character. If you don't specify the ESCAPE character, `\' is assumed.
String Description
\% Matches one `%' character
\_ Matches one `_' character

mysql> SELECT 'David!' LIKE 'David\_';
-> 0
mysql> SELECT 'David_' LIKE 'David\_';
-> 1