Most flowers air-dry best when they are just beginning to open. They will continue to open slightly as they dry, and a fully open flower may lose its petals. This method works best for small, sturdy blossoms, such as lavender or larkspur. Wilting and pest damage becomes more obvious after drying. Choose only the best flowers, and pick extra in case of problems. The flower is ready when the petals are crisp to the touch. Occasionally a bunch will take longer than four weeks, usually because the room isn't ideal or the flower petals are unusually thick. The stems usually dry completely straight. If you want a more natural, curved look, submerge the stems in warm water until soft. Bend them however you like, and hold them in position with weights until they dry again.

How would you rephrase that briefly using Vietnamese?
Hái hoa. Đợi từ 2-4 tuần.