Perhaps you should try some spelling variations:
cam thuc » am thuc, nam thuc, cam thu
te sach » toc sach
cuu tre » cau tren, cau treo
hang di » hang doi, hang vi, hang dien
va hang » van hang, va nang, va lang
thuc va » thuc vat, thuc dan, thuc day
cua tre » cua te, cua triet, dua tren
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
so sanh » do sanh
ve cam » ve cham, ve cac, va cam

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

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