XSL 1.0 : Using Translate(string, from characters, to characters) instead of characters how we can do replace with word

Question

I am using XSL1.0 here i am using word "THO THOR OFFSET" here currently i am suing translate('THO THOR OFFSET','THO','THB'). I am getting output "THB THBR BFFSET". Instead of character to character replace in in xsl 1.0 my out should be display "THB THB OFFSET". How we can do only matching word replacement in xsl1.o.

Could you please let describe the steps please.

We should accept output is "THB THB OFFSET"