I'd a sense that searching domains spending time a lot more than as always in mysql. really domain title column includes a unique index though query appears slow.

My real question is should i become binary mode?? say md5 hash or something like that??

Normally keeping the domains inside a "VARCHAR" data type, by having an UNIQUE index defined for your area, is easily the most simple &lifier efficient method of controlling your computer data.

Never use any complexity (like using Binary mode or "BLOB" data type), with regard to one / two area(s), because it will further deteriorate your MySQL performance.

Hope it will help.