Perhaps you should try some spelling variations:
dia thanh » gia thanh, dinh thanh, gian thanh
da thanh » dao thanh, dat thanh, dam thanh
tai cua » thai cua, tai cuc, tri cua
so sach » so sanh, bo sach, co sach
sach ly » sach y, sach lo, sach ty
nang xa » nang x, lang xa, nang ma
ly nang » ky nang, ly hang, ly vang
cua tre » cua te, cuu tre, cua triet

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 ly nang xa hoi. hieu ((va cach) or (va cac)) thuc ((dia thanh) OR (da thanh)) tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ly nang xa hoi. hieu ((va cach) OR (va cac)) thuc ((dia thanh) OR (da thanh)) tai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ly nang xa hoi. hieu ((va cach) or (va cac)) thuc ((dia thanh) OR (da thanh)) tai cua tre".
• Adding a wildcard symbol may retrieve word variants: so sach ly nang xa hoi. hieu ((va cach) or (va cac)) thuc ((dia thanh) OR (da thanh)) tai cua tre*.