Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
toc sach » hoc sach, doc sach, thuoc sach
tuc van » thuc van, truc van, tuc va
cam tuc » cam xuc, cam tu, nam thuc
hieu ve » hieu va, hieu van
xay hoi » xa hoi, tay hoi, cay phoi
xo dang » cao dang
ve cam » ve cham, ve cac, va cam
o dang » do dang, so dang, o dong
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: toc sach ((o dang) OR (xo dang)) xay hoi. hieu ve cam tuc van thanh ((vi cua) or (dai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((o dang) OR (xo dang)) xay hoi. hieu ve cam tuc van thanh ((vi cua) OR (dai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ((o dang) OR (xo dang)) xay hoi. hieu ve cam tuc van thanh ((vi cua) or (dai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: toc sach ((o dang) OR (xo dang)) xay hoi. hieu ve cam tuc van thanh ((vi cua) or (dai cua)) tre*.