Perhaps you should try some spelling variations:
dieu tra » dieu tri, dieu cua
dao hanh » dao thanh, dang hanh, ban hanh
tang hoa » hang hoa, tang ha, tang ho
tu sach » thu sach, te sach, tu cach
thu dao » thuy dao, thu bao, thu lao
hieu ve » hieu va, hieu van
hoa hoi » khoa hoi, hoa hoc, hoa doi
ky tang » ky nang, ky dang, kho tang
su sach » so sach, vu sach
ve nam » he nam, va nam, le nam

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) or (su sach)) ky tang hoa hoi. hieu ve nam thu dao hanh ((dieu tra) or (kiem tra)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ky tang hoa hoi. hieu ve nam thu dao hanh ((dieu tra) OR (kiem tra)) tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) ky tang hoa hoi. hieu ve nam thu dao hanh ((dieu tra) or (kiem tra)) tre*.