Perhaps you should try some spelling variations:
van hang » van khang, van hoang, van thang
cham xuc » cam xuc, chat xuc, cham soc
cau tren » cu tren, dau tren, ca tren
doc hoc » duoc hoc, duc hoc, hoc hoc
sach ky » sach y, sach ty, sach kem
hieu vu » hieu va, hieu ve, hieu su
vu cham » va cham, vu kham, tu cham
xuc van » duc van, luc van, vuc van
toc hoc » toan hoc, duoc hoc
sac ky » cac ky, sai ky
va cau » van cau, va cac, va dau

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: thu ((sach ky) OR (sac ky)) nang ((doc hoc) OR (toc hoc)). hieu vu cham xuc van hang va cau tren~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ky) OR (sac ky)) nang ((doc hoc) OR (toc hoc)). hieu vu cham xuc van hang va cau tren".
• Adding a wildcard symbol may retrieve word variants: thu ((sach ky) OR (sac ky)) nang ((doc hoc) OR (toc hoc)). hieu vu cham xuc van hang va cau tren*.