Perhaps you should try some spelling variations:
khai luoc » hai huoc, hai luom, dai luoc
dan khanh » dang khanh, van khanh, dat khanh
dan hanh » dang hanh, dan thanh, ban hanh
vu sach » vu bach, su sach, vu khach
va khai » van khai, va khao, va kha
nang ma » tang ma, sang ma, nang cao
vi cua » vai cua, di cua
cua cu » cua chu, cua cau, cua su

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 x) or (nang ma)) hoi. lieu va khai luoc ((dan hanh) or (dan khanh)) vi cua cu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach y ((nang x) OR (nang ma)) hoi. lieu va khai luoc ((dan hanh) OR (dan khanh)) vi cua cu.
• Adding a wildcard symbol may retrieve word variants: vu sach y ((nang x) or (nang ma)) hoi. lieu va khai luoc ((dan hanh) or (dan khanh)) vi cua cu*.