Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
dieu cua » dieu tra
van hanh » van thanh, ban hanh, van anh
dang xay » dang van, van xay
cham xuc » cam xuc, chat xuc, cham soc
xuc van » duc van, luc van, vuc van
va cham » va chat, va tham
hieu va » lieu va, hieu qua
lang xa » lang ha, lang van
de cua » le cua, te 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 thieu ((lang xa) OR (dang xay)) hoi. hieu va cham xuc van hanh ((de cua) or (dieu cua)) tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach thieu ((lang xa) OR (dang xay)) hoi. hieu va cham xuc van hanh ((de cua) OR (dieu cua)) tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach thieu ((lang xa) OR (dang xay)) hoi. hieu va cham xuc van hanh ((de cua) or (dieu cua)) tu".
• Adding a wildcard symbol may retrieve word variants: toc sach thieu ((lang xa) OR (dang xay)) hoi. hieu va cham xuc van hanh ((de cua) or (dieu cua)) tu*.