Perhaps you should try some spelling variations:
cam thuc » am thuc, cam thu, can thuc
danh doi » danh di, thanh doi, dung doi
dan danh » van danh, han danh, ban danh
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
so sach » so sanh, co sach, hoc sach
doi cua » dai cua, hoi cua
nang xa » nang x, lang xa, nang ma
bo sach » co sach, hoc sach
y nang » ky nang, ly nang, v nang
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((so sach) or (bo sach)) y nang xa hoi. hieu van ((cam thuc) OR (nam thuc)) dan danh doi cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (bo sach)) y nang xa hoi. hieu van ((cam thuc) OR (nam thuc)) dan danh doi cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) or (bo sach)) y nang xa hoi. hieu van ((cam thuc) OR (nam thuc)) dan danh doi cua tu".
• Adding a wildcard symbol may retrieve word variants: ((so sach) or (bo sach)) y nang xa hoi. hieu van ((cam thuc) OR (nam thuc)) dan danh doi cua tu*.