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
nam thuc » nam thuoc, am thuc, nam thu
tu sach » thu sach, te sach, tu cach
hieu ve » hieu va, hieu van
tang ho » tang cho, tung ho, tang ha
ky tang » ky nang, ky dang, kho tang
su sach » so sach, vu sach
ho hoi » hoc hoi, hoa hoi, hoi hoi
ve nam » he nam, va nam, le 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 tang ho hoi. hieu ve 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 tang ho hoi. hieu ve nam thuc day nhanh ((dieu tra) OR (kiem tra)) tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) ky tang ho hoi. hieu ve nam thuc day nhanh ((dieu tra) or (kiem tra)) tre*.