Perhaps you should try some spelling variations:
day nhanh » day thanh, duy nhanh, dac nhan
dieu tra » dieu tri, dieu cua
thuc day » thuc dan, thuc vat
dang hoi » dang khoi, dang hoai, dong hoi
nam thuc » nam thuoc, am thuc, nam thu
tu sach » thu sach, te sach, tu cach
hieu he » hieu ve, hiem he, hieu le
hoi hoi » hoi hoc, hoc hoi, hoi doi
ky dang » ky nang, ky danh
su sach » so sach, vu sach
he nam » ha nam, nghe nam

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (su sach)) ky dang hoi hoi. hieu he nam thuc day nhanh ((dieu tra) or (kiem tra)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ky dang hoi hoi. hieu he nam thuc day nhanh ((dieu tra) OR (kiem tra)) tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) ky dang hoi hoi. hieu he nam thuc day nhanh ((dieu tra) or (kiem tra)) tre*.