Perhaps you should try some spelling variations:
sang tai » hang tai, sang tao, tang tai
dang van » hoang van, hang va
toc sach » hoc sach, doc sach, thuoc sach
nang tai » hang tai, tang tai, nang cao
sach ty » sach y, sach tu, sach thu
hieu va » lieu va, hieu qua
xuc van » luc van, vuc van, xuc ban
duc van » duc va, duc tan, duc manh
van cua » vang cua, ban cua, dan cua
va cam » va cham, va cac, va cao
cua tu » cua tuc, cua su, cua cu

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 ty ((nang tai) OR (sang tai)) khoa. hieu va cam ((xuc van) or (duc van)) dang van cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty ((nang tai) OR (sang tai)) khoa. hieu va cam ((xuc van) OR (duc van)) dang van cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty ((nang tai) OR (sang tai)) khoa. hieu va cam ((xuc van) or (duc van)) dang van cua tu".
• Adding a wildcard symbol may retrieve word variants: toc sach ty ((nang tai) OR (sang tai)) khoa. hieu va cam ((xuc van) or (duc van)) dang van cua tu*.