Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
va trinh » van trinh, va tinh, lap trinh
trinh vi » trinh va, trinh ve, trinh viet
su sach » so sach, vu sach
ty hang » ly hang, ty xang, thi hang
van dau » van dao, phan dau
vi cua » vai cua, di cua
cua tu » cua tuc, cua su, cua cu

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 ((ky nang) or (ty hang)) xa hoi. hieu van dau (nuoc or quoc) va trinh vi cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ky nang) OR (ty hang)) xa hoi. hieu van dau (nuoc OR quoc) va trinh vi cua tu.
• Adding a wildcard symbol may retrieve word variants: su sach ((ky nang) or (ty hang)) xa hoi. hieu van dau (nuoc or quoc) va trinh vi cua tu*.