Perhaps you should try some spelling variations:
trinh vat » trinh van, trinh luat, sinh vat
hieu van » hieu va, thien van, lieu va
va trinh » van trinh, va tinh, lap trinh
tu sach » thu sach, su sach, te sach
ty nang » ky nang, ty xang, ly nang
ty hang » ly hang, ty xang, thi hang
van dat » van dao, van dau, dan dat
vat cua » mat cua, bat cua, dat cua
cua su » qua su

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ((ty nang) or (ty hang)) xa hoi. hieu van dat (nuoc or quoc) va trinh vat cua su~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ty nang) OR (ty hang)) xa hoi. hieu van dat (nuoc OR quoc) va trinh vat cua su.
• Adding a wildcard symbol may retrieve word variants: tu sach ((ty nang) or (ty hang)) xa hoi. hieu van dat (nuoc or quoc) va trinh vat cua su*.