Perhaps you should try some spelling variations:
vat danh » va danh, van danh, luat danh
cam thuc » am thuc, nam thuc, cam thu
su sach » so sach, vu sach
vai cua » dai cua, hai cua, lai cua
hieu va » lieu va, hieu qua
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
so sanh » do sanh
va cam » va cham, va cac, va cao
vi cua » di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) or (so sanh)) ky lang xa hoi. hieu va cam thuc vat danh ((vi cua) or (vai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sanh)) ky lang xa hoi. hieu va cam thuc vat danh ((vi cua) OR (vai cua)) tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (so sanh)) ky lang xa hoi. hieu va cam thuc vat danh ((vi cua) or (vai cua)) tre*.