Perhaps you should try some spelling variations:
trinh vat » trinh van, trinh luat, sinh vat
may trinh » may tinh, lap trinh, quy trinh
hieu van » hieu va, thien van, lieu va
hoc sach » hoc sinh, hoc cac, hoc anh
vat cua » mat cua, bat cua, dat cua
duc may » duc mau, duc man, duc manh
lam duc » lam duoc, pham duc, nam duoc
van lam » van nam
so sach » bo sach, co sach
so sanh » do sanh
cua tre » cua te, cuu tre, cua triet
x hoi » xa hoi, o hoi, x ho

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) or (so sanh))) or (hoc sach)) ky nang x hoi. hieu van lam duc may trinh vat cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((((so sach) OR (so sanh))) OR (hoc sach)) ky nang x hoi. hieu van lam duc may trinh vat cua tre.
• Adding a wildcard symbol may retrieve word variants: ((((so sach) or (so sanh))) or (hoc sach)) ky nang x hoi. hieu van lam duc may trinh vat cua tre*.