diff --git a/lua/lualine/utils/loader.lua b/lua/lualine/utils/loader.lua
index ef9d159..d8e5547 100644
--- a/lua/lualine/utils/loader.lua
+++ b/lua/lualine/utils/loader.lua
@@ -224,8 +224,8 @@ end
 local function load_theme(theme_name)
   assert(is_valid_filename(theme_name), 'Invalid filename')
   local retval
-  local path = table.concat({ 'lua', 'lualine', 'themes', theme_name }, sep) .. '.lua'
-  local files = lualine_require.rtp_searcher(path)
+  local path = table.concat { 'lua/lualine/themes/', theme_name, '.lua' }
+  local files = vim.api.nvim_get_runtime_file(path, true)
   local n_files = #files
   if n_files == 0 then
     -- No match found
diff --git a/lua/lualine_require.lua b/lua/lualine_require.lua
index 4d86887..6aa35f7 100644
--- a/lua/lualine_require.lua
+++ b/lua/lualine_require.lua
@@ -35,7 +35,8 @@ function M.require(module)
     end
   end
 
-  local paths = M.rtp_searcher('lua' .. M.sep .. pattern, true)
+  pattern = table.concat { 'lua/', module:gsub('%.', '/'), '.lua' }
+  local paths = vim.api.nvim_get_runtime_file(pattern, false)
   if #paths > 0 then
     local mod_result = dofile(paths[1])
     package.loaded[module] = mod_result
@@ -45,20 +46,6 @@ function M.require(module)
   return require(module)
 end
 
-function M.rtp_searcher(file, once)
-  local ret = {}
-  for _, dir in ipairs(vim.api.nvim_list_runtime_paths()) do
-    local path = dir .. M.sep .. file
-    if vim.loop.fs_stat(path) then
-      ret[#ret + 1] = path
-      if once then
-        break
-      end
-    end
-  end
-  return ret
-end
-
 function M.lazy_require(modules)
   return setmetatable({}, {
     __index = function(self, key)