I've chose Snivy as my starter, and my Team is Servine Lv 33, Zebstrika Lv 31, Watchog Lv 31, Stoutland Lv 32 and Panpour Lv 31 and I can't get through the 5th Gym, please help me!

That's because Servine and Panpour are the only two Pokemon are able to do a good amount of damage to his Pokemon, you need a stronger Water type and maybe a Ground type as well.

That's because Servine and Panpour are the only two Pokemon are able to do a good amount of damage to his Pokemon, you need a stronger Water type and maybe a Ground type as well.

 

So I should train my Drillbur?

a you need a fighting type and a fire type and get your team to atleast level 35 except sevine get him to evolve at level 36

I'd be best for you to switch out Zebstrika for a Fighting type, as Electric Pokemon are weak against Ground types. You can use Servine with a Grass-type move on Palpitoad for a nice 4x super effective hit, and then use the Fighting type and Panpour to take down Krokorok and Drillbur with their fighting and water attacks.

I had my Servine to leaf tornado and Leaf blade Clay's pokemon, if that fails, have panpour surf or scald them >

Scald helps if you can get that burn