Perhaps you should try some spelling variations:
cam thuc » am thuc, nam thuc, cam thu
va trien » va truyen, va thiet, va tuyen
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
thuc va » thuc vat, thuc dan, thuc day
y nang » ky nang, ly nang, v nang
ve cam » ve cham, ve cac, va cam
ca tre » ca tren, cua tre, va tre
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 y nang xa hoi. hieu ve cam thuc va cac bai ((((ca tre) or (va trien))) or (ca tru))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang xa hoi. hieu ve cam thuc va cac bai ((((ca tre) OR (va trien))) OR (ca tru)).
• Adding a wildcard symbol may retrieve word variants: su sach y nang xa hoi. hieu ve cam thuc va cac bai ((((ca tre) or (va trien))) or (ca tru))*.