Perhaps you should try some spelling variations:
cam thuc » am thuc, nam thuc, cam thu
dan loai » dang loai, phan loai, nhan loai
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
thuc va » thuc vat, thuc dan, thuc day
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
ve cam » ve cham, ve cac, va cam
va dan » ca dan, va dao, va dau
ca tre » ca tren, cua tre, ca tra
va tre » va trien
tru » truc

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 ty nang xa hoi. hieu ve cam thuc va dan loai ((((ca tre) OR (va tre))) or (ca tru))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty nang xa hoi. hieu ve cam thuc va dan loai ((((ca tre) OR (va tre))) OR (ca tru)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty nang xa hoi. hieu ve cam thuc va dan loai ((((ca tre) OR (va tre))) or (ca tru))".
• Adding a wildcard symbol may retrieve word variants: su sach ty nang xa hoi. hieu ve cam thuc va dan loai ((((ca tre) OR (va tre))) or (ca tru))*.