Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
cam truc » cau truc, nam truc, lam truoc
hieu van » hieu va, thien van, lieu va
vu dinh » quy dinh
vu sach » vu bach, su sach, vu khach
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
van cam » van nam, van lam, van cau
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach y ((nang xa) or (nang ma)) hoi. hieu van cam truc ((vu dinh) or (may tinh)) vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach y ((nang xa) OR (nang ma)) hoi. hieu van cam truc ((vu dinh) OR (may tinh)) vi cua triet.
• Adding a wildcard symbol may retrieve word variants: vu sach y ((nang xa) or (nang ma)) hoi. hieu van cam truc ((vu dinh) or (may tinh)) vi cua triet*.