Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
cau thuc » cau truc, cuu thuc, can thuc
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
vai cua » dai cua, hai cua, bai cua
lai cua » dai cua, hai cua, lai chau

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky nang xa hoi. ((hieu ve) or (hieu qua)) cau thuc va hanh ((vai cua) OR (lai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang xa hoi. ((hieu ve) OR (hieu qua)) cau thuc va hanh ((vai cua) OR (lai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang xa hoi. ((hieu ve) or (hieu qua)) cau thuc va hanh ((vai cua) OR (lai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang xa hoi. ((hieu ve) or (hieu qua)) cau thuc va hanh ((vai cua) OR (lai cua)) tre*.