Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
hanh vai » hanh vi, hanh tai, hanh van
nang xa » nang x, lang xa, nang ma
cac duc » cac du, cao duc, cac dac
duc van » duc va, duc tan, duc manh
ty nang » ky nang, ty xang, ty hang
sach ty » sach y, sach tu, sach thu
hanh va » hang va, hanh vi
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach ty nang xa hoi. lieu va cac duc van ((hanh vai) or (hanh va)) ((cua tre) OR (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ty nang xa hoi. lieu va cac duc van ((hanh vai) OR (hanh va)) ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach ty nang xa hoi. lieu va cac duc van ((hanh vai) or (hanh va)) ((cua tre) OR (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: hoc sach ty nang xa hoi. lieu va cac duc van ((hanh vai) or (hanh va)) ((cua tre) OR (cuu tre))*.