Perhaps you should try some spelling variations:
thuc dan » thuc hanh, hoc dan, thuc vat
hieu van » hieu va, thien van, lieu va
cam thuc » am thuc, nam thuc, cam thu
xanh di » vanh dai, xanh tai
danh di » danh du, danh dien, danh gia
sach ty » sach y, sach tu, sach thu
su sach » so sach, vu sach
van cam » van nam, van lam, van cau
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
cuu tre » cua tre, cau tren, cau treo

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

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