Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, cau treo
van cham » van chat, van tham, va cham
hieu van » hieu va, thien van, lieu va
cham xuc » cam xuc, chat xuc, cham soc
nang doc » nang luc
doc hoc » duoc hoc, toc hoc, duc hoc
sach ky » sac ky, sach y, sach ty
va hanh » van hanh, va thanh, va danh
hanh va » hang va, hanh vi
ca tren » cu tren, la tren, co tren
xuc va » duc va, tuc va, luc va

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 (cac ky)) nang doc hoc. hieu van cham xuc va hanh va ((cau tren) OR (ca tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ky) OR (cac ky)) nang doc hoc. hieu van cham xuc va hanh va ((cau tren) OR (ca tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ky) or (cac ky)) nang doc hoc. hieu van cham xuc va hanh va ((cau tren) OR (ca tren))".
• Adding a wildcard symbol may retrieve word variants: thu ((sach ky) or (cac ky)) nang doc hoc. hieu van cham xuc va hanh va ((cau tren) OR (ca tren))*.