Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
xang dau » hang dau
luu van » cuu van, luan van, luu hanh
luc van » luoc van, duc van, luc va
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach kem
dau hoi » cau hoi, dai hoi, dan hoi
sach ty » sach y, sach tu, sach thu
cuc tre » duc tre, cua tre, cuu tre
va cam » va cham, va cac, va cao

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) or (sach ty)) xang dau hoi. hieu va cam ((luc van) or (luu van)) thanh tai cuc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sach ty)) xang dau hoi. hieu va cam ((luc van) OR (luu van)) thanh tai cuc tre.
• Adding a wildcard symbol may retrieve word variants: su ((sach ky) or (sach ty)) xang dau hoi. hieu va cam ((luc van) or (luu van)) thanh tai cuc tre*.