Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
toc sach » hoc sach, doc sach, thuoc sach
dinh dau » dinh dat, dinh du, danh dau
cham tuc » nham thuc, pham thuc, cham soc
thi van » thi lan, thi hanh, thi nang
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
va dinh » van dinh, va kinh, va tinh
ty nang » ky nang, ty xang, ty hang
dau cua » dai cua, day cua, cau cua
cua tre » cua te, cuu tre, cua triet

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 xa hoi. ((thien van) or (thi van)) ((cham tuc) OR (tham thuc)) va dinh dau cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty nang xa hoi. ((thien van) OR (thi van)) ((cham tuc) OR (tham thuc)) va dinh dau cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty nang xa hoi. ((thien van) or (thi van)) ((cham tuc) OR (tham thuc)) va dinh dau cua tre".
• Adding a wildcard symbol may retrieve word variants: toc sach ty nang xa hoi. ((thien van) or (thi van)) ((cham tuc) OR (tham thuc)) va dinh dau cua tre*.