Perhaps you should try some spelling variations:
vat hanh » vat thanh, van hanh, va hanh
te sach » toc sach
lang xa » lang ha, dang xay, lang van
ve cham » va cham, ve chat, vu cham
cua duc » cua tuc, cua nuoc, cua quoc
y lang » o lang, _ lang, tay lang
ve cam » ve cac, ve cai, ve cau
va cam » va cham, va cac, va cao
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach y lang xa hoi. hieu ((((ve cam) or (va cam))) or (ve cham)) thuc vat hanh vi cua duc~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y lang xa hoi. hieu ((((ve cam) OR (va cam))) OR (ve cham)) thuc vat hanh vi cua duc.
• Adding a wildcard symbol may retrieve word variants: te sach y lang xa hoi. hieu ((((ve cam) or (va cam))) or (ve cham)) thuc vat hanh vi cua duc*.