then why i cant buff my secodery skills to 200
When you reach level 24, your secondary skills are capped at what your lowest secondary tag is.
For instance, you tag (1) small guns (2) first aid and (2) traps. By 24 your small guns is capped at 250, your first aid is capped at 200 and your traps is 155. All other secondary skills are capped at 155, and cannot go any higher.