<header>
       <button name="mymod_lich" string="Lịch" states="new" class="oe_highlight" type="workflow"/>
        <button name="mymod_nguyenlieu" string="Nguyên liệu" states="lich" class="oe_highlight" type="workflow"/>                    
          <button name="mymod_negotiation" string="Xem xét" states="nguyenlieu" class="oe_highlight" type="workflow"/>
          <button name="mymod_won" string="Đồng ý" states="negotiation" class="oe_highlight" type="workflow"/>
         <button name="mymod_lost" string="Không đồng ý" states="negotiation" class="oe_highlight" type="workflow"/>
         <field     name="state" widget="statusbar" statusbar_visible="new,lich,nguyenlieu,negotiation,won,lost"/>
 </header>

My buttons on workflow display in 2 lines .How can i display it in only 1 line .I don't have enought karma to post image so please see my image in link below.Thanks

http://i.imgur.com/QUI78eY.jpg