Solutions of making cookies less crumbly and dough not being able to be shaped into balls? I made cookies from a YouTube recipe but it was too crumble even before baking. 

The ingredients are: 


900g plain flour
300g sugar
Half teaspoon salt
1 tablespoon baking powder
350 ml oil
Cinnamon


It's baked at 240 C for 15-20 mins.

See the video GHRIBIA COOKIES.

What are possible solutions like what kind of ingredient shall I add without affecting the taste?
Ghribia cookies are meant to be extremely tender and delicate. Making them with just oil is tricky. The dough will be slightly crumbly and difficult to work with. If they're too crumbly to shape at all, then you need slightly more oil until the dough is just workable. Recipes that use some butter or even an egg yolk are easier to handle and stick together easier. So for this particular recipe, add slightly more oil (it won't take much, so be careful). And in general, if you want an easier recipe look for one with butter (or vegetable shortening to avoid the butter taste) or egg.